i haven't played enough games to really give a good opinion on all of these, but hear's my initial thoughts.
free upgrades: while i assumed at first this would be a train wreck and just not fun wen first approved, i was very proven wrong after my first game with it. i loved the change in pace it brought to the game, and how newer players were a lot more willing to take risks and go out. the unlocks need to be adjusted a bit i think, but that's higher level and can be discussed later.
anti-camp: a good start, i think there needs to be a bigger reward for kills away from a base, but at the same time, i still like the idea of setting up and rotating between different offensive (small) forward bases.
simple momentum: i like how it sped up the change of pace of the game, but at the same time it took away a lot of motivation to build (wasn't that much before tho tbh). changes to building that promote fast paced gameplay around multiple parts of the map would be needed.
unlocked buildables: not sure, while it definitely simplifies building, and allows for more balanced early game when aliens get maras, i still feel like it's very bland and linear. i think it may be worth looking into a research based system for building like other rts games (dumbed down a lot though, simple is good), especially with the induction of free upgrades, to keep some sort of economy system going.
build-point pools: like this a lot, haven't played around with it much myself, but i could notice the more instantaneous results that occurred from building, which again, was great for making the pace of the game faster.
simplified locational damage: definitely thank this was a much needed change, the day of floor head bite dretch is finally over!!! but really this brings the difficulty of aliens down a lot, dretches no longer have to be played in a very careful and awkward fashion to reach it's max potential, and makes flanking a much more interesting mechanism as well. perhaps it could be expanded upon a bit more, but for now this is a great change.
construct anywhere: really have no idea how i feel about this one, there really hasn't been enough of a building initiative to see how it actually turns out, i think i like the idea on paper though.
removal of stamina: this change i am really not a fan of. it contradicts a lot of things, the previous changes set out to fix, such as making the pace of the game faster but making humans slower??? also considering headbites are no longer a thing, jumping infinitely doesn't help much either, and bunnyhopping really isn't a viable movement option for humans due to the geometry of most maps, and the nature of the game itself.
this may be biased as i have played for quite a while and gotten a pretty good feel on how to move effectively using the old sprint/stamina system, but it feels as if a vital mechanical aspect in what more experienced players could use to leverage the game (or rather, skirmishes) in their favor has been removed. i feel like not being able to sprint and move effectively seriously limits what i can do early game, even after trying to adapt to the change and attempt to alter my movements, in early skirmishers aliens have an impeccable advantage, and when i could usually counter pressure with pressure and give the aliens a choice between defending or going for my base, due to this change, now it's very hard to have any hope of putting pressure onto aliens early, and humans are kind of forced to just take what happens to them early game and hope for the best.
i think i could understand where this change came from in attempt to simplify movement, as it does take quite a while to learn how to effectively move, but i do not think this is the way to go with it.
overall, i think all these changes with the exception of stamina seem like a good start. i'd really like to play a game with stamina turned back on and the rest of the changes and see how it turns out.