WA is definitely worth getting. Personally, I think it's actually way different from any of the other expansions lol. But your questions. If worse comes to worst and one of your destinations doesn't work, it's still definitely worth getting the expansion. Nectar making and martial arts are two of my favorite things to do in the sims.
Usually, a fresh game won't have any travel problems, but when I had the photography bug, a fresh game had it as well. The thing is, though (and I know it will be a pain) if you get one of these more serious bugs, back up your saves and do a clean reinstall. I had both of these bugs and thanks to reinstalling and clearing my caches I no longer have them. However, if your travel destinations, still don't work try switching active households briefly. It's a simple trick that (along with the reinstall and cache clearing) saved my games.
A tip for when you do travel, though. I hate going more than two sim days without saving, so instead of saving over your original file, while vacationing, save in a separate file. Say your game save is Sunset Valley. When you vacation, don't save over this save, click the save as button and name it SV 2 or something.
I've never downloaded anything from Origin, but I'll take a look at it and see what the shipping deal is.
