I've seen a lot of complaints about different things on the forums, but many of the issues I really see no need to keep raising complaints.
Mostly people complain about bots. Sure, they exist, but are they seriously breaking your experience of the game that much? I don't think so. I go through every delve I find and most of the time there are several bots at the boss. I get my few blows in, loot if I can, get the XP for completing the dungeon and leave, move onto the next quest. What I don't do is get my laptop out and write a forum post ranting about bots.
I see people moaning about maintenance windows. Yes, they can take several hours, but wouldn't you rather have bugs removed from the game? They usually put on a forum post to announce when it's going to happen as well, or were you expecting a phone call?
I see a lot of threads about bugs. Fair enough, post those, but don't nerdrage about them, because that's unconstructive. Make sure you have /bug'd it. Post about it to raise awareness, and then wait.
The biggest thing I notice which is true for all of these posts, is the lack of patience the average ESO (or at least forum poster) seems to have around here! Seriously, chill out, get some fresh air. Things will be ok. (/reassuringhug)
The biggest thing I enjoy about the game, besides the lore, quests and adventuring, is socialising. I notice a lot of players saying they'd rather play solo. Why? Why buy an MMO? Seriously. I am in a good friendly guild. We chat a lot and it's one of the biggest reasons I keep playing.
Feel free to flame away.