Hi, I meant to say something yesterday, but a shiny object or something flew by.
First off, is that a typo, or are you using 5gal kegs?
The only major problem I see with your design is that there needs to be a valve after the pump to regulate flow rate. Are you planning on using your rims unit as a tankless water heater during the sparge? If so, make sure you've got an element with enough wattage to handle that. I'm sure there was something else, I'll chime in again as it comes to me.