Welcome to AC! I’ve been biamping my 3.6’s for years (maybe decade). Everyone is correct that Maggie’s are brutally revealing of the equipment that you use. I haven’t tried an Emotiva, but I’ve used Odyssey’s, Bryston’s, ModWright’s, and now Pass X250.8. I’d say the sound quality improved in the same order for the mid/highs in my system. The bass panel gets crossed over around 250Hz or so in my system, and I’m using subs. Therefore the bass amp’s damping factor is important if you’re using a speaker level output to subs. I’m using a pair of 7B SST’s for that duty. There’s nothing like having 1.4kW at 4 ohm into each 3.6 and then using 3 REL subs for two channel listening.
Finally, the crossover is extremely important when biamping. I used a Marchand XM44 for years and even modified that. I replaced all the 2134 opamps with Burson Vivid V6’s, changed some caps to BlackGates and even added a Bybee. I like watching my Hakko warm up in seconds and floating Cardas solder.

Unfortunately, the Marchand is not even close to the Pass XVR-1 that I’m using now.