That's fine if the guy can do it, but he has a lot of work ahead of him - you may want to find out how much he's going to charge you to do this.
I'm assuming that you are using a good quality mics so you need a good mic transformer and they are not cheap. If you can't find anything decent then try the 3195 from Sowter, which run about thirty bucks.
As far as saturating the output tubes, I'm sure that will sound good on something - maybe bass or snare. I would still take an extra output from VR2, just in case you want a cleaner sound at some point.
Anyway, I wish you all the best!