Hi punman
Glad to see you're back in the world of coin collecting! What to collect is always a matter of interest; after all, it's your collection and you're the one who will get the enjoyment of putting it together. Myself, I love varieties, and I collect small penny varieties because there are so many of them and most of them are fairly inexpensive, as well as available. Yes, there are the expensive ones (you noted the 54 NSS and the 55 NSS yourself), but the majority can be had for less than $20, depending on condition. I also like a collection that will take me a long time to put together; the hunt and the chase of the elusive ones over the course of many years is something that I treasure. I think I would lose interest quickly if all I had to do was buy 70 or 80 easily obtainable coins and then I was done.
If you do decide to go after the varieties, but you don't know which ones, then pick something that really calls out to you. There are literally thousands of them, a great deal of them fairly minor. I have nearly a thousand small cent varieties, a lot of them which will never make the major books. Do I get excited when I find a penny with missing serifs on the 3rd E of the obverse inscription? You bet I do, although I realize that that is not everyone's cup of tea. But that's what makes this hobby so refreshing and interesting; there's room for everybody to have their own particular slant on their own pursuits. There's no right way, no wrong way, and remember you can always change your horses in the middle of the stream.