I'm going a different direction with my rating for the overall sets, and also factoring in which set I would be most likely to afford/buy. They're all great, though.
Mixed THC - who the hell has 6 racks of Claim Stake $5s and a Rack of Empress Secondary Hundos!? The OP, that's who.
Casino Cancun - for the set breakdown & play-ability for a big 1/2 or 2/5+ game, matching molds, and 10 whole racks of workhorse $5s! More chipes=better. (and maybe even affordability in comparison with other sets, I think, but I don't really know what these sold for or would sell for)
Carnevale Cardroom - a unique mixed set no one else has; love the pink tri-moon $5, & Jerry's Nugget $1 for the $100, but admittedly I'm not a huge fan of the chip used for the $1 chip
PCA - a set everyone has seen photos of before; and what a mess this set is-- mismatched mold on the $1, only 5 racks of $5s, an empty barrel in the rack of $100s, and don't even get me started on the cost/price of these chips--expensive!
P.s. If I was just rating the $5 chip in each set, then I'd go:
PCA, Mixed (Claim Stake), Carnevale, and Cancun.