I am not sure how different BC Chromata is from Lyve, but looking at my samples in front of me, Lyve and Epson Exhibition Canvas Matte looks to have about identical weave pattern to me. The fabric might be the same but the coating is definitely different though. Epson looks whiter than Lyve.
Lyve is one of the smoothest canvas I belive, so I don't know if you can find much better than what you got currently?
[OK, I compared them to Epson Satin sample as well, and it "looks" coarser than Epson Matte. It looks like the fabric pattern itself is the same (small weave) but the satin/gloss coat they put on top seems to accentuate the texture hence looking coarser.]