Depends if you want mats or gold. Only caveat is that if you don't have eso + then space for mats could be a concern. I've got loads of both gold and mats so I sell white and grind up green or better.
At max level, I sell all tradeable set pieces that are already in my stickerbook on the guild traders and put anything that my other characters can research into the bank. Everything else gets deconstructed.