Is were will be an opportunity for using mod to change spiders models to crabs or something else, like was is some mods for Skyrim. Because for me its very important, i almost stop playing skyrim cos of spiders in caves, and continued only then such mod was released....

Well, from what I've seen the spiders in ESO look nothing like the ones in Skyrim. In fact, I find them looking rather silly at times.

Hopefully you can avoid them all together, since mods like those will most likely break the UDLA agreement as 3rd party program in MMOs.
But I encourage anyone who has access to beta or have a twitter account if they can ask this question.