Not at all, if you have the DLC then you can also use this:
Additionally it provides +10 accuracy instead of -10 like the heavy armor and that’s not all, it also gives you double weight capacity and 30 armor. A pretty nice choice for snipers with this perk and you’re free to crossclass to anything you want, for instance berseker to get also armor break or infiltrator for double damage, very strong in my opinion.
Mostly but also without proficiency for mounted weapons the rockets are more inaccurate (not sure, but i think -50%), so they scatter way more as normal.
A sniper with this perk, his armor and the mentioned bionic body augmentation above is capable of hitting mostly direct where he aims, pretty accurate.
I do it mostly exactly the opposite to get more versatile builds. See above, just mix the right things together.