Sounds to me like you’re just experiencing newbieness. Mixed with “I play WoW and this game sortof looks like it”-ness.
What mobs are hostile? Mobs with red life bars are hostile. Mobs will yellow life bars are not. Some “hostile” mobs threaten to attack first (and can therefore be run past if you don’t dawdle), but that’s something that you’ll just need to discover. It’s usually pretty logical (wild boars and some bears threaten to attack first, orcs, not so much).
There is no “average aggro proximity”. It depends on your level and the type of mob. Wargs will attack you from a long way off, as will archer type enemies, while you can get a lot closer to ye-average goblin before he’ll go on the attack.
Why are you running between quest hubs so much? I have no clue. Did you make a hobbit? The Shire is kinda sprawling and the quests there involve a lot of travelling, but that’s the price you pay for doing hobbity style quests - you’re a lot less likely to need to go kill ten rabid wombats/collect 12 squirrel tusks in the Shire. Instead you’ll be delivering mail, recovering spoiled pies, or otherwise running errands. Sure, there’s some “clear out the wolves that have overrun my farm!” stuff, but there’s a lot less of it. If you don’t like the diffuse playstyle there, I A) Question your Tolkien Geekery, because I don’t know what else you’d expect there and B) Suggest you try either creating a different character in a different area, or just hop on a horse and travel to either Bree or Thorin’s Gate and try the quests there instead.
I can’t offer you anything about the controls. They recently sped up combat so you don’t have to wait for auto-attacks between skills the way you used to. The game -is- a “queuing” based combat system though - if you push a button while a skill is executing you do, in fact, have to wait for the previous skill to finish before the new one executes, even though (and I know this is gonna be a tough one for some MMO vets) there’s no little “progress bar” for how close to do you are swinging your sword. Some classes do have “induction based” skills where you get to see the little bar for how far done you are singing your song or whatever, so maybe playing a class that actually acts slower would help. There is a deliberate amount of “between skill lag” in combat - you can’t just chain from one attack to the next to the next unless the attacks are designed to let you do that. If a skill says “fast” it will ignore this lag, if a skill says “immediate” it will even interrupt the animation of the previous skill and launch right away, but as a rule, skills take time to execute and have some ‘recovery’ time during which you can’t launch another. I suggest you leave your other MMO experiences at the door, if possible.
I disagree that geekdom is remotely a handicap, unless you’re going to complain that it did not, in fact, take you three days of real time to run across The Shire. Yes, there are concessions to standard MMO conventions (there are a lot more monsters in the world than there ‘should’ be) but in terms of lore and feel, the game does a very good job.
What level are you? I suggest you try a different race/class combo. And be sure to follow the ‘epic’ quest line (the ones that list as “Volume 1, Book 1, etc” in your quest log), since those are the ones that are particularly going to play to the story driven strengths of the game.
Really though, it sounds to me like it’s the opposite of your geekness that’s getting you. I’d say the fact that you’re used to a comfortable with WoW is causing the differences (which are, in fact, just differences, and not anything related to the quality of either game) to grate on you because things aren’t how you expect. Try to forget about “How WoW does it” and just play LotRO. You’ll find it’s an equally good or better game even though it doesn’t work the same way (in spite of the superficial similarities).