Hey Zero Static,
It's likely that I will loop back to existing series and also beef them up a bit more. For sure itch lacks a lot of high quality asset content, but it's also hard and time intensive to produce. Generally I agree that I also would like to offer a lot more assetpacks, it just needs more sales but the production speed over the years got faster anyways =)
And I also understand the difference between hobbygamedev and more professional gamedev, that's why I started the more NES inspired sidescrolling series, which was aimed at a lower price/quality ratio, but that also was only built up to 4 tilesets and 2 characterpacks and there is a lot of air/potential for enhancement and improvement. How is that series for you as a hobbydev?
Yes you can make as many prototypes from the assets as you like. If you are playing around and giving away the games to friends etc. to test it doesn't matter.
As soon as you put a game on itch or another store using the assets or you make a kickstarter campaigns thelicence you bought for gets used up for it, because you have the possibility to earn money from the game (tips in case of free games or the buying price)
I hope that answers all your questions.