That could be a really great combination, and should be tried. Switch it at the set break for a comp.
I think it helps to balance the trim pots of the minime before the show. I found it tricky to get the trim pots balanced in the field. It is much easier to generate a tone or white/pink noise, either directly into the minime or via mics. You can then balance by looking at the meters (tweak the source output so the next meter light is *just* starting to light, etc), or sending the earphone out of the minime into a PC or a better metering device. Once you have the balance set, just be sure and make the same changes to each trim pot.
Since you will be controlling gain with the aerco, it does make me wonder what trim level sounds best on the minime. Are the trim pots attenuators? Would it be best to turn the pots all the way down, run mid, or all the way up? That'd be good to know.