I always approach it weighing the options on how to do my show while making as little "changes" for the house crew. I have an act where only the lead vocalist needs an in ear mix....the house crews can always handle that from the supplied monitor console and I can get by without extra setup at FOH. The whole show is set up for the headliner. I would make myself as easy to deal with as possible at every turn.
John, you bring up a couple of things that deserve comment/expansion when viewed through the eyes of a *regional* provider.
I've always encouraged support acts to be "opener-friendly". For me that means having every aspect of their show designed to have the lowest impact on the headline artist's show and technical resources. Sometimes that means "sure, bring your own mixer" and sometimes it means "hey, we can give you 12 channels on the main desk." With the ubiquity of IEMs even at the lower levels of touring, I really like it when support acts have their own monitor desk (usually a rack mount mixer like a MixWiz, ProHouse or 01v96, etc) and they hand us a split.
Bringing your own FOH mixer & snake, though, can be a problem if it hasn't been advanced. As Mike A points out, FOH real estate is a precious commodity and getting space for a console may require consent further up the food chain than the headline act's BE.
I think you're right, John, that support acts at the regional or local show levels benefit from presenting a low-impact technical footprint. What makes up the "low impact" part is variable, however, and advancing phone calls and emails are important so everyone in on the same page come day of show.