Upfront fee for planning vs ongoing AUM percentage fee

I am struggling with how to implement an upfront fee for financial planning.  My initial interaction with a new client/prospects is to develop a financial plan. 

Most of my revenue is from asset based fees with a little commission from an annuity or alternative something.

Nearly everyone I do a plan for becomes a client, and I have a pretty firm asset minimum so I get paid eventually for the planning.

However, it seems it would be cleaner if I charged an upfront fee for the plan to cover that work and waived the AUM fee for 6mos/year to not double charge the client.  My BD doesnt let me waive that advisory fee for a couple of months of course.  Although, an RIA custodian will let me do what I want with fees.

Should I consider going all RIA for the flexibility?  or Should I just live with the situation that seems to be working, but isn't as "clean" as I would like?

Any thoughts or ideas would be appreciated. Thanks