The short answer is no - I'm finding it enough work just to implement my one player goals! And once the one level demo is out, although I'm expecting that'll be final code for the bulk of the game, I can then begin developing the 14+ levels and I'm tentatively budgeting another year for that..
Oh, shame... maybe some time in the future?
Neuro/Mustang
I really need to upgrade before I can release. So from what you've written (Mustang), it sounds like a vid card and OS upgrade would be a good temp measure before a full machine replace.
Oh yeah. A half-decent vidcard should make all the difference (probably much more than a faster processor in your case) - my game runs fine on a 400mhz processor (or even less?) but NOT with a crappy gfx card.
When you do upgrade your whole system though, you should keep the old box - very handy to check downwards-compatibility on!