Hey James,
I couldn't agree with you more on a few new sub catagories in the chips section of eBay. Looking thru 4000+ lines can be rather tiersome for an old codger like me. BUT eBay has a great search, and advanced search that I have used for years that works very well, providing the SELLER PUTS in those KEY WORDS that will put their
chip(s) into the catagory you are looking for. Me, I personally have four searches saved in my favorite places (AOL). Large Crown, Reno, Reno OBS, and CA card room. It seems to work for me, BUT every once in awhile a really nice chip is just listed as "A CASINO CHIP" and has a very brief description, or none at all, and you miss out one that really good one. What it boils down to is educating the sellers as to how to list their auctions and to give a detailed account of the item they are selling.
I have a friend who tried to get eBay to create a new sub-catagory several years back. He succeded, but only after several hundred emails from his fellow collectors. You can try that route by starting an email campaign and hopes it gets some attention at Customer Service at eBay.
Have a good one, I'm still looking for Large Crowns, the cheap ones