More ±, neutral.
Deceptor, Hell Cannon and almost any armor shred and damaging afterward are mostly more effective.
Yes, that’s their special case.
More -
It would be very situational. I mostly never have a sniper close to any enemy and then it depend what an enemy that is. You can be way more effective against all minor Pandas like Arthrons and Tritons with 2 x quickaim and any other weapon.
I personally have actually limited my 8-man team to only ONE sniper rifle, otherwise I will sweep away all pandas before they are even within range. I may be able to use SR with my style of play particularly efficiently.
I even banished rage burst for SR, because in my opinion absolutely unfair / broken. But we already had that 
What difficulty?
On normal (veteran?) after the early game, when I get the higher ranks, I take not more than 3-4 squaddies in my teams but not limiting me to hard by using the OP abilities or combinations. This way I realized, that SR are not really THE best weapon in the game but only situational. A 3 man sniper only team will have a pretty hard time.
That’s what I was getting at. The only time SR are the wrong answer is when you have a swarm of enemies and you can’t possibly hit them all before it’s too late. But lately the DEVs reduced the number of foes we generally face. At least in the game I played lately, less than 10 foes is the norm.
One thing most players answering the thread have forgotten; weapon balance isn’t just about how much damage we can do with them, it’s also what happen when we are on the receiving end of it. Triton with SRs are quite a pain, especially if they can vanish as well.
Note:
The weapons that are efficient in your hands are just as dangerous in the hands of your opponents!
Can someone disagree there too? 
True, but I almost fear the Iconoclast Tritons more because they simply oneshot my soldiers and they are pretty fast. One sniperhit is manageable but one Iconoclasthit mostly not.
SR can kill enemy from mid game with two shots only. With double use quick aim. If you shot once - you never kill anyone. So SR is in balance at least. At end game sniper’s main advantage - paralyze SR. With common SR it don’t cost too much in combat.
Second heaviest (hero?)
Yes, with 8 snipers only it would be more difficult.
But if I have 4 snipers, it is easiest for me, especially on big maps, where the big boys appear.
When thinking about balancing, we need to consider how things stand right now, especially when we know that some sort of balance changes will be implemented, but we don’t know which.
Also, these are not necessarily “broken” builds. A 25% buff to damage & accuracy of ARs perhaps warrants being replaced with something better, but it’s not really broken.
It’s part of the game design that weapons utility largely depends on the characters wielding them and how they use them. There may be adjustments, but this approach in general is not likely to change. And the point with SRs is that they benefit less from the skills & gear of the characters wielding them than other weapon types.
Regarding the table, unfortunately it’s only of partial use. First, accuracy and mobility are basically the same thing in PP: the capacity to reduce distance to target is the same as increasing accuracy, and both can be buffed a lot.
Regarding armor, it’s more nuanced than mid game enemies have 20 armor, late game enemies have 40 armor. For example, Chirons never have any armor on the heads. Crabs and Tritons, especially after Leviathan, tend to have much less armor and even in the late game have spots covered by just 10 armor.
And then again, you have to take into account the use of combined tactics: you are not going to shoot your AR at a highly armored target. First you will strip the armor using any of the multiple ways available, and second you will attack with the weapon that delivers most damage… And that is not going to be a SR.
SRs = easy, very suboptimal. Nerf them to be less “easy” and I don’t know where that will leave them taking into account the game as it currently is.
On that note, @conductiv I think the changes you suggested elsewhere to accuracy/damage/mobility buffs is really the right direction for balancing. As long as the hellcannon can be used with laser point accuracy and as a hammer and as everything in between…
And with such a team on an Anu heaven defense in their slums? I think mostly a waste of capacity because any other weapon will be more efficient in this case.
As I said, situational are SR the best choice.
On large open maps like citadels for sure: the more sniper you have the best you go, because you will almost fight on long range.
Never been on the receiving end of a shotgun (point blank) yet, I usually manage to dispatch them first. On other hand Nergal’s Wrath pistols are my bane…
I’m never that concerned about “killing” that foe so much as to remove the most troublesome attacks or abilities it has. Crippled foes are far less of a threat, and SRs are really good at this. The way I play, I usually try to disable my foes first, then move in to finish them off. Work better when I do have 1-2 SRs on my team.
No one said we can’t carry any other weapon.
No, sure, but again: “Sniper Rifle, the ultimate answer to any foe”?
I say no, not more.
Another EDIT, maybe it is more understandable what I mean:
But if I have 4 heavies with boomblast and Goliath, it is easiest for me, especially on maps with many obstacles, even when the big boys appear.
Goliath with boomblast, the ultimate answer to any foe?
No, almost any unbalanced teamsetting (or skillcombo) is an answer to certain circumstances, because they are situational strong.
The game offers you several options how to play the game. Multiple skills can be combined and what do you scream? Sure, sniper nerf. Next up is probably vanish or berserker, right. All OP, nerf them all. If you realize how good a technician is, damn it, they need to be nerfed. Try to put more variety in your game instead of making it worse.
I’m not crying for a NERF so much as to give all weapons an equal opportunity to shine. SRs in my mind are just too useful to not carry around, and not having them makes the game much harder (for me at least).
Small example. I started a new game yesterday on Hero level of difficulty. So far the game has been going well and i’m building up my squad with new recruits. Today I ran into a scavenging mission against The Pure, 5 of them. I had to abandon that mission since my squad of low level soldier would not have managed to save any containers and might have lost them in the process. My sniper was left home to heal so all I had was ARs, handguns, one Hel and some grenades. If my sniper was there I might have tried to fight them of, but without I felt the odds were stacked against me… Especially since 2 of The Pures had SRs.
Use grenades, a lot of them, their armor really don’t like that and you can beat them mostly with grenades and ARs. Peek out, throw grenade or shot and peek back or use high ground at closer range to your advantage and especially against their snipers. That is the real tactical game I like a lot, but to be honest, it also takes some time …
For me a Heavy with Goliath is the best answer to enemies snipers.
With a sniper you mostly have to be in LOS and this makes him very vulnerable to their snipers. In my book not really the best choice. It would be maybe faster, but also with high risk for your sniper.
And you make wrong conclusion, that SR is OP. Right conclusion is: enemy with 30+ armor on all body parts in the very beginning of the game - awful work of game devs.
I have to agree with you!
Yes, it’s a NO-BRAINER
The decisive thing in comparison to Shootgun, AR, Pistol, Meele is that you don’t need a Superhero with “max SP”. (no extreme mobility, no level 7 skills) exactly like the SR.
These weapons are also the most dangerous or even unfair on the opposing side (sniper-tritron, bomb / acid chiron, …) or not?
Edit: My attitude to this is exactly the same as here:
I think the main thing that is coming out of this discussion is not that the SR is the ultimate king of all weapons, but that there is a hell of a lot of variety in the methods you can use to kill Pandas.
Heck, from this thread alone, I hear ‘Heavies with Goliaths’, ‘Deceptors with aim buffs’, ‘Shotguns with Dash’, ‘Pistols with Rage Burst’, ‘Tritons with Iconoclasts’, ‘Hell Cannon shredding armour’, ‘Synedrion Auto-Rifle’, ‘Hell Cannon with Sniper/Heavy accuracy buffs’, ‘Nergal’s Wrath at close range’…
Oh, and ‘Sniper Rifle with Quick Aim’.
So no, it’s clearly not everyone’s ‘ultimate answer to any foe’ - though I personally loved my 3 snipers with Synedrion SRs (and my Infiltrator with SSR double damage) in my playthrough.
For me, it’s fine as it is. It’s powerful, for a given style of play - and I absolutely refuse to combine it with Rage Burst, which I think is an abomination - but it’s not OP, and it’s clearly not the no-brainer weapon of choice of many players on this forum.