There was a poll on patreon way back when where Grizz asked if he should do smaller/slower updates (can't remember which) with full CGs or do sketches with more progression. Sketches won the vote, probably for the best considering i'm pretty sure the early CGs are going to get redone to be inline with the future sprites.
CG poll: https://www.patreon.com/posts/assets-moving-31560689
Very old preview of new sprites for tyson & sal: https://www.patreon.com/posts/sprite-reworks-29670294