It would really depend upon the individual and what they value. I would want harder to find chips from my area and someone else might want something from their collecting area.

I would think that Gardena chips are the most collectible (or most collected) because many were made by TR King. You should probably be looking at 1 off’s samples in different colors.
The Normadie Club chips (knife and fork)...I don’t believe there has ever been a denomination above $1 found in that series...so a $5 could be someone’s holy grail.

My Holy Grail would be one of these Gold Coins from Artichoke Joe’s (octagon).

I was told they were solid gold and taken off the tables when gold prices started increasing.
Also..pretty much any of these other high denomination chips on this brochure.

I also would like both of these chips....

Most people...well nobody really....knew that these AAG chips are connected to Artichoke Joe