Well we're about two months away from an expansion, that gives you plenty of time to get a character to 50 and clear the story if you're interested
As for healers, Conjurer (White Mage) generally puts out the biggest heals and is simpler to use, while Arcanist (Scholar) gets some neat tricks - like a healing pet - and rarely worries about running out of MP.
I dunno if I can definitively say it's still worth playing for you... 1-50 is certainly the most linear part of the whole deal, and other than the story it can be a bit boring at times. That said it's still a chance to explore the game and that can be interesting for its own sake on the way to the level cap. Once you hit that point, there's a ton of neat things to do and the experience changes dramatically (for the better in my view)
So I'd say go for it
Sounds pretty cool. I've been looking for an excuse to get into the game anyway, and this is enough to get into it. Is the free company guide here still good, or will it be easier to PM someone in game? I've never joined an established FC before. I hope the guild is active/friendly :D