Here's my unsolicited feedback from building out a basement game room:
Pool tables take up an enormous amount of space. They are hard to move, expensive to have set up and do require costly maintenance if you use it regularly (new rails, re-felting). If you have a pool table, make sure that radius is clear of all obstructions. Nothing worse than playing pool via "house rules" because the table needs a cheater stick, etc. due to improper clearance. Have space for two spectators chairs on the wall next to cue rack. A small ledge on the wall to sit drinks on will be the best thing you can ever do in the proximity of a pool table. It discourages the inevitable guest (or family member) that sits a drink on the table and ruins the felt. If you love pool, it's a great thing to have. If you want it because it's "cool" or seems to be the thing to have, you will regret it. Buy a good table. I mean an antique Brunswick. Everything else is shit. 9'. 8' in a pinch. Bar tables (7') are like shooting on a postage stamp and 10' are unwieldy and only for really serious players. You can get a really nice antique Brunswick for $2-5K depending on your taste. CL and FB marketplace are your friends.
No darts with the pool table. Put dart board next to bar. It's a pub game after all. Spend the money on a good commercial electronic dart board, ideally with a computer player like a Valley IQ. Game does the scoring for you. You don't have to have someone else to play/practice. And soft tip only, particularly if you have kids. I'm not a fan of steel-tipped darts. They bounce out and will put a hole in something you value at some point (personal experience here). Buy 4-6 sets of reasonably good darts ($50-70 per set) and have an ample supply of flights, tips, etc.
I will throw out a wildcard. Shuffleboard. They are huge. But they are absolutely gravitated towards if you have parties. It's an easy game to immediately grasp and takes no real skill to start (but a hell of alot of skill to play well). A close second? Ball bowler. I swear, people who won't touch a pin or arcade will run up to these things.
I think you have dedicated far too much room for the gym and will regret it down the line. Literally everyone I have ever known who has dedicated gym space stops using it. You may be a dedicated body builder, so your mileage may vary. But a massage table area? That's another pin or seating.
Lots of seating. Seriously. If you are building this as your Fortress of Solitude, cool. More power to you. But most people like to show off their stuff and/or use it as a social hub. You can NEVER have too much seating. Not enough seating discourages people from camping out and enjoying themselves. A dedicated theater loses extra seating because it is walled off from the rest of the basement. Dedicated movie spaces are a space hog. Multi-use theater spaces are more efficient.
There you go. Advice you didn't want and probably think is terrible.