It should be that easy.
However, there are some routers that flat will not work.
Had a Linksys myself - with issues - Linksys tech support told me that their routers do not work with Mac's - and this from one of their supervisors. Had no Win based wifi to check it against - so ended up getting a newer d-link n router that works great.
There are a whole bunch of regulars around here that are using Linksys routers without issue. Hopefully, you'll be in that group and when you first boot up with your Mac, it'll just go through the process, ask for your password and you're up and running.
Sounds like you try to anticipate problems and be prepared for them up front. You may be over worrying. Have found that most things pretty much "just work". Since you're doing without a notebook at all right now, wouldn't worry about it until you get your MBP and see what happens. It all may be for naught.
For a little reading, you might want to check out cwa107's threads in the
faq section on both networking and printing. I did end up having to get a new printer. But after my forays into Linux, I expected it. Have made the decision not to buy peripherals any longer that are not multi-OS compatible without full knowledge of that fact up front.