OK actually I can answer the question - I did take down a couple dropped ceilings on the first floor. The second floor for whatever reason had ceiling plaster in really pretty good condition, unlike the first floor
The kitchen ceiling was the worst - under furring strips there was nothing salveageable, plaster too far disintegrated.. Worse case scenario like that is you have to hire someone to demo/drywall the ceiling (ceiling only - walls generally are in better condition cos the gravity isnt pulling down the plaster so much.) Use corner tape between ceiling and walls, and then do a nice skim coat over ceiling so it looks more like real plaster instead of drywall.
I cant remember what I paid for it but it went pretty fast - he rented a lift device and the drywall was up in no time. Just get some estimates for however many ceilings you want to take down - so if you HAVE to hire someone, you are prepared for the possibility. I guess having grown up in an old house Im not quite sympathizing with this apprehension that something might be askew or in need of repair in an old house. It kinda comes with the territory. You just need to work it into your budget, along with mortgage payment and utilities and etc.
Re the panelling, you could just paint it a nicer, lighter, brighter color - using proper primer it should adhere pretty well and it can give you a cottagey plank wall kind of look. Then.... after youve been in the house for a while, start to experiment with removing some panels and just see what you find - we wont tell anyone