Do you think it would be good to open the Construction Set for people to develop new stuff? It will not be modding, since the ESO staff will curate all the information and select only the good stuff to be on the game. Like DOTA2 is doing.

I would say that it is a good idea to do that, so the devs can get some fresh input from the community. But only if it sticks to pre-established lore. I don't want to be able to ride dragons because some guy pitched it to the devs and they thought it would be cool. I highly doubt that would ever happen, though

Even though I think this would be awesome it will never happen because this is an MMO. Everything needs to be the same for everyone as far as content is concerned. But giving ideas to devs thats what the forums are for.