Can you give an idea of the salary ranges/industry of the direct hires? For your temp positions, do you have a specific time frame or are they long term contract?
We place mid to senior level candidates in the education industry (Higher Education & K-12). Salary range is usually $80,000 to $120,000. We charge 25% fee to our clients. Our temp business is used by our clients for their lower level positions (Admissions Counselors, Financial Aid Reps, etc.) and the terms are usually 90 days to perm.
I've heard about standards being 5% commission off the fee, with about a base of $30k for entry level (1-3 yrs). Keep in mind every region is different for an appropriate starting salary, but for entry level, I'd like to see them produce before raising the base. For the temp positions, a weekly commission based on either the 'profit' or a lump sum based on the hours worked. For example, $40 for every 120 billed hours per week, or something like that. The percent of commission doesn't necessarily need to increase or be progressive, as your recruiters grow with you, they will build pipelines of candidates resulting (hopefully!) in quicker turnaround times, etc.
Just a few thoughts that come to mind. If you want to talk about these, please don't hesitate to message me privately and we can talk. I sent you a connect request, if you're interested.
Good luck to you!