Subpanel for finished basement: sizing, cable, installation advice

Thanks in advance for advice! I just finished framing my basement and am moving on to electrical. Hoping for advice on the subpanel. Main 200A Eaton panel is in the garage. I'll need to run cable up into the attic, cross about half the house, then down into the utility room in the basement. I haven't measured this yet, but I'm guessing about 80' of cable. The basement is about 2200 sf with 2 bedrooms, 2 bathrooms, a wet bar, living room, workout room, utility closet, and large storage area. I haven't finished my drawings yet, but I'm guessing about 15 circuits if I do separate lights and receptacles in most rooms. Mini-fridge, small countertop microwave, and a treadmill are the only notable loads. Everything else will be pretty standard: 2 bathroom GFCIs, bar GFCIs, and a bunch of lighting and receptacle circuits. No heat, range, freezer, AC, etc.

My research is telling me it's much better to "go big" and overdo these things, so I was thinking of installing a 100 amp panel with 24 spaces (48 circuits) from Square D, using a 100 amp breaker at the main panel, and running 1-0/1-0/1-0/2 SER since I'll be crossing insulation in the attic. I also understand the subpanel will need a ground bar installed. Is this overkill for my situation? It's a large basement, but without a fridge, range, baseboard heaters, etc., am I overdoing it? I definitely don't want to run out of space down the road, but I also don't want to spend $2+ per foot on cable (plus wrestle that monster) if half that would do the job.

Anyone have opinions or advice for me? Also, do I sound like I know what I'm talking about enough to attempt this on my own and live to tell about it? 🙂 Thanks!