My thoughts on your posts are that low valued chips are hard to deal with because of associated expenses with each item driving the costs up. So, in addition to your list, I would add: Make groups of chips 3~5 that have some commonality and sell as a lot. That reduces listing fees, individual shipping, etc.. Still list better chips singly.

1.) Quality of pictures: ABSOLUTELY!! And show both sides.
2.) Time of day: I would use early to mid-evening. People off work after dinner, relaxing. Less busy.
3.) Day of week: Yes, Wed through Sat are my best days.
4.) Tight window: Yes, but not too tight. It is aggravating to miss an item and want to bid on an alternate/back-up that closes within minutes. I would suggest staggering ‘like items’ 20 to 30 minutes so unsuccessful bidder can grab his second choice item.
5.) Mix: Not so important I think. What is important is to have a nice list of other chips so buyer can ‘impulse buy’. “I won that chip, I migh as well bid on these other two and combine shipping.” say some buyers.
6.) S/H: BE REALISTIC…. Over charging will turn off a buyer quickly. If he thinks you will screw him out of a nickel then he knows you will screw him out of a dollar!
7.) 99¢: Is a good start. Some chips don’t bring much over that…. Sell THEM in a lot rather than individually. Can cause competition on a lot if two buyers are competing on different specific chips in that lot.
8.) Length of auctions: Most/many people wait to the end to see what the REAL price is going to be. Shorter is better, but not less than 5 days. You need exposure to buyers without making them wait too long and change their mind and buy elsewhere.
9.) Description: IMPORTANT to many, a short blurb may catch the eye of a buyer and pique his interest. Don’t write a book, just a short 4~5 sentence (accurate/true) description.

Just my opinion…. I have been buying/selling since 1996.