Thanks again to everyone for your advice on replacing my gear. I ended up with the D7100, 18-55, 55-3300, and the 50 mm AIS. I still have to replace the 35 mm 1.8G, but may have to wait a bit to have the necessary cash on hand. In the interim, I also have to replace my flash -- which is the question I am posing here.
I use flash rarely. Mostly just for taking pix of family indoors from time-to-time, and on the occasional tour of a museum or interesting old house. This said, I of course regretted on the first day that I had my new gear that I didn't have a flash as I was a bit far back at my daughter's school closing ceremony and ended up with some shots that were much darker than they would have been if I'd had something other than the on camera flash availble to me.
My old flash was an SB-400 and it seemed to do the trick, although I sometimes thought a bit more oomph might've been helpful. So the question on the table is whether to replace it with a used SB-400, an SB-500, or whether there's a strong case to be made for something more powerful. If the latter, and keeping in mind that I'm cash poor right now, does anyone have a strong 3rd party recommendation? I've searched the forum and find lots of thoughts re complex flash setups, but not much re single flash users.
Thanks in advance!