I'm new to VDGG, but KC I've been a fan of for years (decades?). Crimson went through many phases. For the new listener, I would suggest getting the best from each phases. You already have Phase 1 covered.
Phase 2 - Islands (It stands alone, dismiss Earthbound, not essential and poorly recorded.... completist only)
Phase 3 - Lark's Tongues / Starless / Red / USA (live) "Lark's Tongues" is the first of this phase and (I) consider it to be the best, however all three are incredible.
Phase 4 - Discipline / Beat / Three of a Perfect Pair "Discipline" is the one from that series which says it all. "B" and "ToaPP" are more of the same.
Phase 5 - Thraak (double trio album)
Phase 6 - Happy WWYHTBHW (EP) and Power 2 Believe (heard both, don't own either) If you liked Thraak, you may like these also.
Summation:
ITCOTCK - You Own
Islands (Save for later, money's scarce)
Lark's Tongue (Get it)
Discipline (Buy After LTIA)
Thraak and after - (Only if you like Discipline. Belew's voice may or may not be to your taste.)