Isbaluna

You sure can, though the cost of doing so would be out of reach for anyone who's just started the game. Recently I levelled a character 50 levels with crafting, for 5 crafts, so it's definitely possible, 8 of them would be 80. It really is just the cost, it doesn't take long, if you prepare and find a guide for them in advance you would probably take approx. 30 mins each craft (You can do artificing in under 10 minutes.)

The sudden realisation that you did something so stupid that people will refer to foolish acts by your name for centuries to come.

Welcome to Guild Wars 2, hopefully you'll enjoy it more than the end of your time at SWTOR. There's a HUUUGE amount of PvE to explore, and a PvE/PvP mix up in WvWvW if you felt like venturing into that too. Also a Thief born and bred, so if you have any questions about it fire away and I'll try my best to answer.

I play on EU servers (changes every week) so probably won't see you in game, but feel free to add me to your friends list, as far as I'm aware there are no server restrictions on that
IGN: Isbaluna

Like everyone above has said, any class can DPS if given the right build.
Rather than looking at the DPS/survivability of each class, because realistically they can be moulded to whatever you want, look at their "special" abilities. For example Thieves have stealth, Necros have Death Shroud, Elementalists have their attunements so on so forth, and see which one of those you prefer the most, that seperates the classes more than anything in my opinion.

It would probably be better in both cases to simply level the crafts.
For tailoring the price to get from 375-400 isn't particularly high, and the materials to craft your own gears are cheap in comparison to how much you'd pay at the trading post.
For Jeweler the price to get to 400 is a bit higher, but you make that money back by selling the crafted materials you made. The exotic jewelry is more or less the same price to craft as it is to buy, maybe a tiny bit cheaper.

If you need help in getting the last few points in the craft, some of the cheapest ways are here:
http://gw2eclipse.com/jeweller/
http://gw2eclipse.com/tailoring/