Lkdog,
Some answers for your questions.
1) Sure it can be a fun thing to put a new cartridge on your existing turntable, and it will get you by for the short term, while you look for your upgrade path. Nothing wrong with that at all.
2)I think you could get into a decent level of analog playback for around $1k, if you look around and get some good buys on used equipment. For new equipment, it probably will take close to $2k, by the time you get a new phono section/TT/arm/cartridge/cables/etc. There are some good new turntables coming into the affordable range now, from a variety of quality manufacturers, and the $1k TT market is becoming quite competitive. I'm sure you could find something satisfactory in that range now. Maybe a little more for a better tonearm/cartridge wouldn't hurt any.
As you go up the performance ladder, the advantages of analog become more and more apparent. Many users on this forum even feel that a Rega Planar 3 with a basic Goldring cartridge exceeds their more expensive digital players. But I'd consider the Planar 3 to be the bottom rung of the audiophile analog ladder, in real terms. Anything up from there would be better. If you could go up to $2k or more, then you are really getting into what analog can do. Beware, it is addicting.
What you are hearing now is only the tip of the iceberg. You have a mass-market TT, and it can only give you a glimmer of what is there.
