Thats actually the route I think Steam and Beth should have taken instead of the whole paid mods fiasco. If they had gathered up 6-12 mods (a new lands or quest mod to give added content, the unofficial patches to fix up the bugs, a couple of UI mods and several immersion mods and maybe an armor or weapon collection for example) they would have had more than enough content for a huge DLC that could have been offered for PC and consoles, splitting the proceeds with the mod authors. Since they could offer mod content for their console base for the first time the market would have been huge. Even PC players who use mods would benefit as they would get a collection of mods polished and integrated with each other.
If modding for TW3 takes off CDPR could easily do the same - strike a deal with some mod authors and offer an expansion including some of the best mods and making it available to people who play on consoles or even the majority of PC players who never install a mod. If they quietly let the word out that they were thinking if doing that they might even get additional interest from modders, many of whom would be thrilled to see their mods picked up and themselves recognized and rewarded for their efforts. From CDPR's POV they get a lot if people investing time into developing content on spec, and they get to pick among the best of that content to release to a wider audience.
This isn't a good idea
BECAUSE of the recent fiasco. Right now people are going to be highly sensitive to any steam + developer team up over mods. And to be quite honest it isn't needed. The modding community is quite active in games. The reason witcher 2 mod community is rather small was that the game itself wasn't structured for mods well. It was linear, the environments were small, and the mod kit came well after most people had moved on.
Also the "best" mods is totally subjective, often the best or most popular mods can be popular among different group of players. In skyrim there are groups of people that LOVE the immersion mods but there is an other group that absolutely hate them. Some people like the anime mods or mods that create content in the anime style of art, these are really popular but they also have the its anti lore crowd freaking out. In short the modding community is so diverse that some of the most popular mods are considered the best by one group and the worse by a second group.
If console users want mods then they have to as a community start banding together to figure out how to mod a console game. With so much of the content now being stored in HHD in consoles it is happening. I believe there are youtube videos on how to mod ME3 for the xbox. (I recall seeing one but I could be utter wrong about that memory). It isn't the job of the PC community to hand hold the console market to mods.
If redkit arrives with in the next month or two, given its open world nature witcher 3 will draw in lots of skyrim users and with those users modders. We will see the modders come, there is no need to incentives them because the open world nature and vastness of the world is incentive enough for modders.