I'm most excited to hear from Obsidian overall but I eagerly await to hear/see what PlayGround Games and The Initiative are working on (supposedly a new Fable game and a Perfect Dark game which I would love)

Stranger things have happened. Guerilla went from Killzone Shadowfall to Horizon Zero Dawn. 

Rare and Obsidian, followed by Ninja Theory.

Hoping Halo can return to its former glory too.

Well a change from FPS to Action RPG isn't as big as Racing to RPG. But yes it can be a great thing.

Playground games are definitely exciting and full of potential. They've already proven they can craft an amazing open-world racer with Forza Horizon and I hear rumors they're making a massive RPG in the same vein so that'd be great to see. 

Obsidian makes some solid RPGs - a bit on the buggy side at times but they're akin to Bethesda in that the gameplay is such that it's usually worth a few blemishes. 

Not ready to entirely give up on Rare yet. They were my favorite non-Nintendo developer for the N64 and created probably my favorite all-time series in Donkey Kong Country. Even though I don't play much of their new stuff they were the initial reason I made the leap from strictly Nintendo to Nintendo + Xbox. I've gotta believe they still have a little something left, or can have something of a renaissance.

Coalition somewhat lost me with the new Gears games, which just aren't as compelling as the old ones. Still I guess I'd be interested to see some original projects from them. 

343i- What can I say? Halo is my favorite. I'm super pumped to see Halo Infinite!
Playground games- The quality of their games speak for themselves. Forza Horizon is such a great series and I'm excited to see the RPG they are working on.
Ninja Theory- I've enjoyed damn near every game they have released from Kung fu Chaos, DmC, Enslaved, and Hellblade. I know Hellblade 2 will be great and project mara looks interesting.
Obsidian- A company with a stable of great games under their belt. They've never had the full dedicated support so now with the full back of MS, I'm excited to see what they have going on.

under the radar developer is InXile. They've been around forever and I can see them doing some really cool stuff.

Playground (because of the AAA RPG they are working on) and The Initiative (because of super secret project).

I would say Obsidian. Easily the best pick up of all the studios MS purchased.

It’s far more likely MS will farm the IP out to XGS and therefore publish it with a outside developer who specializes in platform games. Platform games simply aren’t as popular as they were in the 90s and any attempt for Rare to make a new Banjo or Conker will never live up to your expectations and especially fond memories. 

Everwild looks whimsical and interesting. I’m not sure about your stance on SoT but today it’s packed with content. No video game comes close to capturing what SoT offers. It has a very dedicated community, you see people post things on Reddit where they craft things you see in the game, it’s nice to see. I just hope you aren’t one of those Rare fans who thinks everything they do now is automatically bad because it isn’t their 90s style platformers. 

The Initiative, what’s their current employee count? I heard less then 100 but I assume they can staff up on temp workers when they have a concrete plan in place. But even with 100 people you can make a AAA game if you have enough time. 4 years at least I’d say (it’s been almost 2 now I think)