I would tend to agree with Craner that the best thing to do if you want a career is to get an agent. Agents have a stake in the game and so they have an interest in selling you to people. It's how people get far in music/show biz, too. Agents make the calls and figure out who'd give you the time of day, which saves you time and rejection. (I actually asked around but could not find any fantasy novel agents or agencies that buy fantasy novels...)
BUT, and this is a really big butttttt--I have a couple of friends who are literary agents who also have contracts, and my bf's dad is a hot shot editor at one of the big U.S. agencies (at an imprint that mostly publishes political stuff, otherwise I would beg for his help). What I can say is that, since your writing is actually interesting and doesn't fall into the more tasteful and bland conventions of contemporary "literary fiction", these types of publishing insiders would probably not be very interested in selling you. Not that they wouldn't like your writing- I think they would, even if it was a little avant-something for them-- just that they'd not think it very salable.
In other words, if you're not Jonathan Safran Foer, you would be miserable around those people. I have spent many an evening with them and I just think you'd gag. If you think that zero books blurb is annoying (cuz it is) you'd think these people were worse, in a different way.
Regardless...Why not just take the solid offer you have and then after that book comes out, shop it around in a portfolio to prospective agents. That's what I'd do.
Edit: Oops, x-post, Eden basically said this too.