As always, a question of how much you are willing to spend. I lived happily with the Basic for a couple of years and eventually upgraded to the Quad QC-24P (valve phono stage by Tim de Paravicini with variable output to enable direct feed into the amp). No question, musically clearly more engaging but for three times the price of the Basic.
Let's stay in that price bracket for a while. If you like to stay in the "family" the new Basic+ is an improvement on the former Basic at about the same price (EUR 500). The crux is, though, you can upgrade with the Accu+ unit (costing as much) and that really pushes it into another league (I've heard this combo fairly often with the Clearaudio Maestro). Alternatively, go for the Symphono+ (EUR 1,000 and again you'll have the possibility to upgrade with the Accu+). And then there is the Balance+. Interestingly, we're now talking the same price level as the Quad 24P, and as it happens the Balance+ has variable output as well! (Again, later battery upgrade possible, although I have no "first ear" experience how much it will bring here). Btw all these are very good with MM as well as MC, should you want to change on that front some time.
Of course, in that realm there are a number of excellent alternatives (fellow Audiogoners will take over from here, I'm sure). One I auditioned together with the Quad was Tom Evans Microgroove Plus. I eventually chose the beautiful flow of the valve unit over the "groove" (what's in a name) of the Evans. A pity the Clearaudio Balance+ wasn't there to compare at the time, I guess it would have been a close contender.
Will that level be AMAZINGLY good? Only you can find out of course. Surely, it will get amazing if you push the budget out even further. Just one more I'd like to mention, then, that has amazed me quite recently: Ayre P-5xe, superbly authoritative and transparent with any kind of music, admittedly with entirely other accompanying gear (e.g. Shelter 901 cart). Twice the price of the likes discussed before, but that is in Europe where Ayre gear is always offered at a very hefty surplus. Perhaps in the US this is a much more viable alternative.
Good luck
Karel