What's my best upgrade options

Just another two cents:  If vinyl is your jam and Rega P6 is about where your budget price point is, take a serious look at the Mofi TT's (i.e.  more bang for your buck).  Also, if you don't already have a record cleaning system I would seriously consider one (i.e.  ultrasonic).

As virtually everybody has suggested, get a new turntable/arm/cartridge.  Plan on spending in the $5 to 10k range.  If that's beyond your current budget, then save up until it's doable.  Don't make any half-step moves!  Also sort out your cables.  Definitely go balanced where applicable and try to stick to only a single manufacturer.  You don't have to spend large dollars to get good sound from cables.  You might even want to sort out the cables first because it will allow you to better evaluate subsequent changes to your system.  Finally, there are better CD players.  Prices vary, but there is good value in Marantz, Denon and Teac/Esoteric models.

Everything I've suggested assumes you have already paid meticulous attention to loudspeaker/listener room positioning.  It doesn't cost you anything but time.

Good luck!

P.S.  Is there really a Capt. Janeway statue in Bloomington?

I recommend that you start with a new cartridge; Ortofon Cadenza Bronze. From there go with a new table, perhaps a Rega P8 if you like Rega. I have a new P10 as one of my tables and I like it very much. After the table, I would begin experimenting with cables.

I agree with those who recommend starting at the source, TT or DAC and Transport. 

Whatever you do, don't waste your money on cables or power cords. As long as you've got OFC cables, nothing you buy will change the sound AT ALL, save for longer runs that may need 12AWG instead of 14/16AWG.