Some answers to your specific questions:

1. ESO academy and Tamriel foundry are great sites for learning the game mechanics. For builds...which tend to focus on vet end game builds...I like alcasthq.com. But at first just focus on having fun and playing how you like. It can take months to learn the game thoroughly...no need to rush to end game stuff.

2. I love nightblades. Fair warning, they're a tough class to learn. But you have tons of mmorpg experience, so that'll help the learning curve (you know what buffs are, you know to wear the right armor, etc). And if you learn ESO through a nightblade, you'll be able to walk into any other class on additional characters pretty easily.

3. Racial choice. Races in ESO have passive skills that generally make them better stamina or magic builds. In this game, you tend to pick one resource type formthat character's attacks, then save the other as a "dump" for buffs.

For example, my stamblade is a ruthless killer. He's invested tons in his stamina, and his stamina based attacks are lethal. Then he also uses magic abilities like dark cloak, grim focus and siphoning attacks. These are buff abilities. They give him something to use his magic on, but they stray away from damage abilities because his magic damage is weak.

If you're looking at stamblades, Khajiit, wood elf and Redguard are very good racial choices. For magblade, altmer, Breton, maybe dark elf.

4. How I feel about ESO

I think it's great, honestly. They're working hard to build it into an MMORPG that will contend as a top player. And they've created a world that is rich in lore, diverse in content, and offers a ton of playstyle options to keep things fresh.

Can they sustain it? Tough to say. We've seen plenty of online games that do well, then a few unpopular moves devastate the game. But they tend to avoid huge missteps, and when they make big moves they're pretty courteous to their players. For example, housing rolled recently. They could have made houses real world money only, or they could have used a system that charged a monthly in game gold fee to use as a sink. But they made houses relatively cheap, and a one time buy in.

There are pros and cons, of course.

Pros

There's a wide variety of "games within the game." Pvp, pve end game and pve questing are the major ones, but there's a crafting game, the selling and gold game, thieving, housing, etc. This offers a lot to do if you take a break from your primary activities, and also attracts a wider variety of players.

The ability and skill tree system is quite extensive and generally good


Cons

Pvp has always suffered from performance issues that can be frustrating. They consistently work to improve this, but it's a persistent issue.

They can be somewhat obstinate about class balance and changing abilities/powers/etc. for example, in the upcoming June patch they're ignoring some skills the community has been rather clear are OP, while they've nerfed some the community has felt are not.