Literally everything in game (except astral loot) is farm-able.
The issue -> 14 day free trial; it'd suck farming and pveing for days just to have an RvR experience of a couple days.
Pre-50: Although people HATE the repeatable quests, do them continuously until you ding 50. They're boring and make the game seem like work; but the additional 5-10p you get from running it will get you on your way to making a template and they are relatively quick levelers (you can stop at high 40's if it gets unbearable to do some other quests that are great in xp as well as loot).
Literally every class now-a-days is played heavily, so there are no real "needed" classes, my suggestion is pick a class you find fun but that can also solo/small man decently... nothing worse then not being able to find a group and have to sit around in region spamming because you can't bomb around solo. Once you pick a 50 my first bet would be to:
1) Start your CL path
2) Start the ML path (you can start this at relatively low level, but until you have about a grand of bps/glass you can't really begin).
3) Get a template
4) Farm for the template; MAKE SURE you have your artifacts in template already, no points farming a template just to have to relevel temps. (this helps CL, loot & sometimes (if you're killing high enough mobs) MLs)
Artifacts: I had some confusion when I first came to ToA from classic too; they're literally items that generally have okay stats but that have some pretty awesome A) ToA bonuses (speed/damage %) B) /uses (example: Bracer of Zo' , a must-have for any class that can run it. It has 2 uses, 1 is a disorient and the other is summoning 3 weak but interrupt heavy pets).
After doing those four things you should have:
Maybe CL 3-4, Maybe ML 3 or so & a template.
You can generally compete to some degree with the completion of that list; plus the more you play the better off you are.
Start your realms LoTM quest line (found in the throne room, you should talk to the same person who started your level 30 champ quests); these are relatively easy, give great CL xp and great loot (for teh poor) which you can in turn buy pieces of template you don't feel like farming or glass for more MLs. They also require heading out into the frontiers and some even require player kills; this helps building up the RvR gamer in ya.
For the first few days; find your realms BG leader (make sure it's a keep taking one; Rescu (alb), Atrebates/Kaptkent (mid) and in hib... you're shit out of luck; don't tag the Kzar bg, or you'll literally just waste time running around aimlessly for the most part, and maybe take a keep is the Rescu zerg's on it already. And take some keeps/towers. Each one you take will be worth some decent rps but more importantly, BPs. Even if you die inside the keep while it's being taken, do not release until your realm takes it. This will help you work your ML path a bit more because each keep is 500-700 Bps if I remember correctly. This saves you time farming glass (especially if you play a PvE weak toon) and instead you can get out there and RvR a bit.
Anyways good luck.
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Davolica, Fru Norsewoman Warlock. AMO Officer
Hayziis, Bantiarna Lurikeen Mentalist. GM Aes Dana
Macrina, Phoenix Knight Briton Cleric.
http://www.boandterri.net/winlok%20guide.pdf <-- My Warlock Guide