Well, I think Phoenix Point will be a different game than Xcom2 (or the Firaxis-Xcoms), not necessarily better or worse, this is up to you to decide which one do you like the best.
The major differences will be the implementation of “physical” bullets, insted of a priori chance determination for shots, and the more strategically relevant geoscape gameplay, more similar to the UFO series (old Xcoms), with multiple bases and so on (not much is known about it yet).
I suggest to go and check the video and press threads on this forum which have a collection of material about Phoenix Point which may be more precise than what we -invested supporters/players- can give you.
And there should be a few gameplays on the recent Backer Builds from both external youtubers* and snapshot staff (UnstableVoltage and Julian Gallop himself)
*At personal level I recommend you RetconRaider, who made quite a few videos about Phoenix Point, trying to analyse what we could expect to see in the game and the lore from the short-stories