I've been keeping our healthcare visits. The way I figure it, routine visits are fairly quick and so exposure is limited. If I let something get worse, it will likely mean more visits, longer time, more exposure, etc. For example, dental office makes me nervous because of the need to remove the mask. But if anyone needs cavities filled or major work done because we waited too long, it will be way more time out of mask than just the routine cleaning/exam. All doctor's offices/dental offices I've been to have been taking really good safety measures.
I say schedule them all now -- most of them will likely need to be scheduled out a ways b/c so many providers are booked way out right now, so you probably won't get in right away. Better to do it all when it's preventative stuff and not emergency care.