You have not told us what model of Pioneer turntable you have. So we do not know how good or bad it is. You also have not told us how much you want to spend. That makes advising you somewhat difficult.
Unless the turntable is damaged or a bottom of the line model, I would think you would need to spend a significant amount of money to get significantly better than what you have.
I personally would be looking for a Technics SL-1200/1210 if I were interested in having a good turntable (if I only wanted 33 1/3 & 45 rpm, unless you can get your hands on a MK4 that also plays 78 rpm):
https://en.wikipedia.org/wiki/Technics_SL-1200
New ones are quite expensive now (since they are no longer being made), but used ones are quite common. People think of them as DJ turntables, but they were designed for high fidelity. They just happen to be very solid and reliable and work well in a DJ environment, so DJ's started using them.
Regarding the other question, it is common for companies to remaster music, so that which version of something one buys will matter for how it sounds. This, by the way, is one of the reasons why some people believe that LPs sound better than CDs, because they happen to like the LP mastering of the music they like. There is nothing at all wrong with the way the CD
format sounds. But if one puts garbage on it, then it will be garbage.