Actually, it might not be the computer that's at fault here. My bet is that this disconnect is due to the DAW, and not the computer itself. I myself went through this when I kept trying to figure out how to integrate ProTools into a compositional workflow...which would never work. As a compositional platform, PT just downright SUUUUUUUUUUUUUUUUUCKS!

Ableton, on the other hand...that's a whole 'nother kettle of fish. It does everything that PT doesn't like to do just fine, and a lot more besides. And if it DOESN'T do what I need, I can fix that, thanks to its integration with Max. It takes far less effort to figure out than PT, too. However, I should note that I like to mix in analog...I just prefer having the sounds under my fingers, so I get that. You might try a "hybrid" setup like that yourself...multitrack in Ableton (and this works so much better with a proper multichannel interface), then mix in analog to a digital 2-track. This way, you get that same incremental control...but you can ALSO make use of outboard processors with ease, which also has the effect of reducing the processor load on the DAW. Sure, it has a learning curve like most anything else, but it works more "musician-ish" if that makes sense.