Definitely the phono stage first. I was holding my turntable back (a lot) until I got an Audio Research PH8. I now have an Audio Research Reference 3. I highly recommend moving to in between these two end points in Audio Research.
I have been upgrading my phono stages since the early ‘80’s, several horrible sounding, highly recommended, budget phono stages, then finally the Audio Research PH2, PH2SE, PH3SE… PH8.