Wish you luck on making a BM a better tank then a Barb, but I do know it's sadly not gonna happen. Barbs get something like a 30%-50% (or more) more hps if built right for tanking (one of the best examples that I had seen was an axe wielder BM (barbs don't get *much* choice there, annoying) built similiar to a tank barb. The BM had in the 8000s for hps, the Barb in the 13000s.) And while grouped they get a whole lot more phys def (neither of us'll ever beat any mage-type class for tanking magic, of course). More so when grouped with a BM (the aura shield is nice. Stacks with the cat form bonus too.) And lastly, and most importantly, tiger-barbs get skills specifically meant for generating a lot of agro. BMs just don't. (Oh, and a skill to cancel other's casting).
It's certainly *annoying*, as when I originally created a BM myself, I wanted to be a tank. Barbs sounded more like the pure damage dealers to me by the description, at least on the MY-EN servers. And honestly, as much fun as switching into the tiger form can be (I actually do enjoy THAT part), I really hate being forced to be a were-creature of some sort. So I do understand your feelings.
Of course, none of this is to say that you CANNOT tank. BMs can tank rather well, really. And the self heal and 30 second defense skills certainly help. But when it comes to the really nasty things and FBs at your level range, you'll end up with no choice but to rely on a barb and be a backup if necissary.
In anycase, welcome to the game, and the guild. Do have fun!