I've actually had a similar issue with Milkyspit when I first commissioned a custom. I had already locked in and prepaid almost $800 worth of funds (including the light host) for the project but it was kinda put on the back of the list for some time. It took around 6mths to complete; which isn't all that long come to think of it but definitely isn't a timeline you can plan around.
The $ locked in wasn't a great prospect either; if I had it in my hands, I would have earned 75% returns within the 6mths, which I really did with the rest of my money in a suprisingly good investment.
I suggested some ways Milky might want "to productize" to cut waiting queues etc.. but a lot of the feedback from CPFers were : "If you want a quality product from an master modder/artist, be prepared to wait". Reference were made to some knife maker whose waiting list stretched to 2 years. I totally understand that; it's just that I prefer not to have my funds locked up for so long with no product.
Anyway, it worked out all good and the product was definitely worth the wait!! Milky rocks!
For your case, Gene chooses to 'randomly' sell his products by the luck of the draw. Similar to other highly acclaimed modders who put up first come first served lists, I don't see anything wrong with it. Especially when no money is taken. They don't want to deal with pre-payments and all that hassle of managing a list. If there are delays, he has to answer. It's his own choice of business practice.
Don't forget when a modder decides to make a batch of items without a pre-order or waiting list, he is also risking being stuck with a bunch of unsold goods if the demand suddenly shifts to something else. So if he chooses that business model, I think it's pretty fair.
I totally understand your frustration, but unfortunately, in this world, demand drives everything. Demand makes celebrities and soccer/football players earn the $$ they do and allow them to turn up their noses at people and enter VIP clubs and start fights. If no one gave a damn about watching movies or sports, this industry wouldn't exist.
So in the same way, some of the custom modders are 'celebrities' in our community; not so much a business. To get in the club, you gotta play by their rules unfortunately.