Sadly, I couldn't do much exploring in this underworld as I was pinned into a small space beneath where the next quest was. Still, it's always entertaining to get a behind-the-scenes look, a bit like seeing the back of a piece of needlework.
ESO is pretty much the same as all the other Elder Scrolls games, to be honest. It doesn't explain key concepts (light and heavy attacks, morphing, enchantments, poison) and every fight is the same because dynamic difficulty adjustment makes it the same. I've been to a whole bunch of different zones, mainly by accident. I ignored the main questline for so long that the game had to railroad me onto it via a staged mugging; I wound up with a full set of trainee armour at level 30.
Every day I log in, I'm given a free gift; the main purpose of these seems to be to fill up my bag space so I have to pay to expand it. I've been playing for a week and a half (I'm level 38 or something) and have spoken to one other player and been in one group (with a person who didn't speak); this is actually pretty good for a newbie in an MMO that has been going for a while. I may even see an invitation for a guild that doesn't have a stupid name and isn't stated in Russian or German. I don't know about doing any party-based dungeons, though, as the other players will think I have more experience of them than I do so I'll have to watch videos beforehand to avoid being kicked out.
Anyway, it's fun in the same way that the other Elder Scrolls games are fun, and I think I'll continue to the level cap. I shan't be splashing out for the Elsweyr expansion, though.