L5R is such that the best way to learn most of the wacky fun mechanics is to sit down and stat up 20 or so characters.
I have shells for 25 different ones, but have only finished one. Fortunately, I took tomorrow off, so I will be able to put 4-5 hours into building them and be ready on Saturday.
As a Crab Bushi, you can easily get to 9k3 damage starting out (and an armor TN of 25, earth ring 3, reduction 3, etc); their biggest weakness is (and always has been) accuracy. As a Crab, you have to watch your attack roll - rolling 5k2 is *not* going to cut it, even starting out. You'll have significant difficulty hitting training dummies.
If you like the Crab Hida Bushi school, you should also check out the Lion Matsu Berserker. Crab Hida are about dealing and taking damage, but have trouble with accuracy. Lion Matsu are about hitting and dealing damage; they are fairly resilient (not as much as the Crab, of course, but better than Crane or Scorpion). Their biggest flaw is being terribly Lawful Stupid, sort-of-vaguely-like Paladins.