I would have to say visual effects only. If relics were substantially better stat wise it would create balance issues with end game content. If the content wasn't designed around them then they would make the battles too much easier and if it was then it might force people into completing the quest which is just too absurd of a grind to force players to do. I don't mind the relic grind, but only if it's optional. I would not continue my sub if that type of grind became mandatory.

I suppose I wouldn't mind additional effects so long as all weapons got them and relics were again not substantially more powerful than the other best weapons at the time.