You can absolutely do everything you need with the M3 Pro 12/36. I think it’s more than enough. I think that getting the Max out of the Max would need a Mac Studio instead of a laptop.
If you want to future proof, 16/64 definitely, 96 is pointless for your workflow.
But the thing is, by the time Pro/12/36 becomes obsolete, M5/6 will probably be a thing and you’ll be better off getting a new machine rather than using an old M3 Max. If I had to bet, those laptops will have an updated look as well so you probably won’t like your old laptop anyway :)
At the end of the day, if your tool is making you money, then the expense is justifiable.
Go get that 16/64 you lucky dog you :)