Thanks for the great response. Much appreciated. Here are the answers to your questions, and some relevant background information I would have provided before if the post wasn't already so long.
1) Definitely. I'm very close with the booker and most everyone else at the club, including the sound crew. I'd definitely have the support of everyone to set up the rig and leave it there plugged into the direct outs on the board. But, they usually do 15 minute set changes and a lot of the time there's only one sound guy (very small club, 125 attendance maybe) so I don't want to ask them to do anything special for me. Despite the extremely small room, they surprisingly do mic everything.
2) I have recorded several hundred shows at this place over the years, possibly approaching 1,000 soon, and have been using a Korg D3200 12-track recorder to take from the board the past 3 or 4 years. In the few hundred shows I've done in that time, I have never once needed more than the 12 tracks the Korg provided (including a room mic track most of the time). However, the board has 24 inputs I think, and depending on which sound guy is in, any combo of 16 or 17 may be used.
The real issue causing me to need more than 12, is that different sound guys use a slightly different board setup. One uses 1-4 (kick/snare/tom/tom) for drums, leaves 5 blank (in case a fifth drum mic is needed), bass in 6, guitar 8-9. Another uses 2-6 (kick/snare/tom/tom/hat), 7 is bass, 10-11 for guitars. Plus similar stuff for vocals and DI's for acoustics and keys and what not.
So I may not ever record a band that needs more than 12 tracks, but since I won't physically be there to select which direct outs I need, I'll have to them all plugged into the recorder.
When I first started recording multi-track from the board there, I took all the vocal mics into one track from the vocal sub group, kind of like you mention below. That sub group was permanently setup, not something special for me. I'm sure it's still like that, but they got a new board since then and I don't think the sub groups have 1/4" outputs for me to plug into any more. Something like that may be an option though to reduce the total inputs needed.
Milo