Welcome justvisiting!

You are going to return to Vegas and feel like you're in a different place now that everything has changed so much! Please give us a trip report when you get back and let us share in your experience.
As for Circus Circus....some people run their mouths about the place, but they either 1) haven't ever set foot in it or 2) haven't set foot in it for a long time. I've stayed there a number of times in both the Tower rooms and Manor rooms and I've never had a problem. The rooms have always been clean. The beds have always been there so I could sleep on them and they even provide pillows and towels! I think you're going to be just fine staying there. I was in the casino this weekend and it seems just like it has every other time I've been in there.
As for the neighborhood, I would have no problem walking around in most of those areas and since you used to live there, I'm sure you know where you're going so, unlike me, you don't have to worry about getting lost.
I think you are going to have a great trip and that you've made some good choices...just don't ever stay at the Days Inn downtown (I made that mistake once) and life will be good