1., 2., 3., 5.: You need to consider so many external factors that lead to the decision of what personalized licenses / contracts / models etc you are going to offer. I have another topic here which explores sales / business models on the topic “how to reduce the cost damage of piracy through licenses / models” alone. In the linked post I gave an example of 20 sales models of which the EPIC marketplace only seems to support 1 for 99% of what is on the market, which happens to be costly and vulnerable.
Sales model against game and asset piracy. - #56 by Roy_Wierer.Seda145
You can’t offer your service on the marketplace for X euro an hour to make specialized models, you can only sell an asset of say a fantasy monster that people maybe buy. maybe 3 times if they don’t want to look like X other games. If you totally want to break away from that system you either can’t offer your service on the marketplace or you are selling a plugin which communicates with an external environment, like an AI in the cloud which does translations for you. You can count the amount of marketplace plugins which have such an external functionality on one hand.
Terms and conditions for marketplace sellers state you must support the latest 3 major versions of the engine. Unreal Engine constantly receives updates which break basic functionality and they do not offer an LTS version. This leaves the seller with a potential X amount of bugs to work around per version per product and deal with the reports, regardless of if you have 3 customers or 5000. I’ve been with UE4 from the start, now UE5 and I can exactly tell how many hours go into fixing nonsense EPIC breaks.
Considering that many people are not using the latest version of the engine, but expect to finalize their project on say version 4.26 (because why turn the core upside down when at 70% of a big game)… This is not something you can support without offering some sort of support subscription or other model for additional income.
Personally I hope the new marketplace will be highly customizable, so that you can show what you want and offer what you want. I like the approach of Fiverr where you can offer a silver / gold package for a service (just one interesting model :)).
Silver: “Get 5 designs, prototype project, source files, 1 hour personal consultant”.
Gold (30% off): “Includes Silver. Let me implement the plugin in your project”.
Because people look for a solution, not all the steps in between. They just want to get the job done and paying for it is usually the fastest + cheapest. That is already one reason why selling asset by asset is not ideal.