Try out a few amps in your local store, if you have the option. My experience with amps is that many are ”muddy” when it comes to synths, especially at higher volume/gain. I personally don’t want my sound ”coloured” by an amp, but to many guitarists their particular amp is part of their sound, because of the colouring it adds. Especially the ”boominess” bothers me. For your band application, I’d recommend going just a bit bigger than you actually ”need”, because imo the boominess becomes especially apparent in the higher gain stages, so push the amps you try out a bit to see how they behave. Depending on the sound you want, of course. In my case, when I played in a band somewhat similar to what you describe, the mid range frequencies often got quite occupied, so my role was mainly adding some power in the lows-lowmids where wanted, and atmospherics in the top frequencies.