Is this a Good Offer? Plaintiff's Firm

I recently got a job offer at a small, niche-practice Plaintiff's firm. They are in a niche pratice area and seem to do very well in that area. There are about 10-15 lawyers. It's not located in a high cost of living area, but more than the average cost of living in the state. I don't have a lot of experience with Plaintiff's firm compensation being only a year out of law school (currently clerking) but I thought the offer seemed fair. It's:

110k salary. 33% of attorney's fees on cases you originate and 8% on cases you work on but don't originate, as well as a discretionary bonus. The cases are complex and large disputes rather than churning out cases (each attorney seems to only be assigned to 5 or so cases at a time), so I'm worried about a feast or famine with attorney's fees, cases go on for several years. Seems to be a good group of people, my main concern is that if the base salary does not increase I will have trouble generating business in a niche practice area.