First off, welcome!

>Its probably worth mentioning that I'm a caster. I know
>there's a recommendation that they're not the easiest classes
>to start out with...

One thing you'll want to remember is that everybody has his own opinion about which classes are "best" for new players. My feeling is that the best class to play is the one you're going to enjoy. If you enjoy role-playing, and hopefully you do, then part of that is the "theme" of the class and has nothing to do with the mechanics and whether they're especially newbie-friendly.

Odds are, whether you play a "good" newbie class or a "bad" one, you're still going to get steamrolled by vets. If and when that happens, don't assume it's because you chose to play a mage class. It's just part of being new to the game.

I don't know what mage class you're playing, but transmuter, shapeshifter and good-aligned conjurer seem like good fits for new players. Possibly invoker if you can handle a bit of skill spamming.

>I also like the idea of having access to identify
>when trying to learn what stuff does.

Definitely not recommending you abandon your mage character, but it's worth noting that mages aren't the only ones with identify. Druids, healers and shamans also get it. Bards and svirfs get lore at 100%. I agree playing a class with identify makes sense when you're a new player. Gaining exploration and observation xp will cause your "lore" skill to go up. Add in a little spam, and you can have it at a useful level before too long.

>Firstly, I think I might just be 'doing it wrong' when it
>comes to trying to level up. I read up on the ranking guide
>and have been using those areas primarily...

Be aware that the level ranges in that guide are rough approximations. It's also super out of date; some of the areas don't even exist anymore. But it's not a bad place to start.

>but I seem to have
>to rest between every kill, which takes a long time. It might
>be that is right, but I'm at that stage where I mostly want to
>just be sure I'm not making something harder than it needs to
>be.

Are you ranking alone? That could be a big part of your problem. Some classes have a much easier time ranking solo than others. Generally speaking, mage classes aren't the best at it. If you join with two other people, you effectively get 3x the hp regen, 3x the mana regen, 3x the damage, plus a boost to the xp you earn for each mob kill. Skills from different classes also synergize. For instance, a transmuter can haste melee classes and slow non-melee classes that spend mana to do damage (in order to boost their mana regeneration rate).

If you can find a group of three, that's almost always going to be better than trying to rank alone. Even if it's just three mages of the same class, that's better than a one mage of that class trying to go it alone.

>Second, when browsing I read that AC isn't that important. Are
>there caveats to that (like if you have x skills etc) or is it
>just a general rule of thumb that you should not worry about
>it that much?

It can be useful at low levels, but once you get above 20-25 it's not something most characters pay attention to. Other things, e.g. stats, hitroll, damroll, spell saves, hp, mana, are generally higher priority.

>Lastly, is there a way for me to get a wield item to parry
>with and not give up my shocking grasp and similar?

Been a while since I played an invoker, but I think the design of those spells is that you need to have one hand empty.