It's a lot tougher when you do both in the same night. I do quite a bit of that, most recently at a dual facility event here in Los Angeles.
I find that one needs about +10dB up on the Subs for EDM, and that I don't really care about going down to 20Hz- the Chest thump is much higher- 80-120Hz. THe Low Mids are often ignored in a DJ setup in favor of Rumble & crap.
Learning Yoru Crossover cold, Going Digitally controlled on it such as an Ashly 3.24c or higher helps- One can adjust by the band if neccessary. I find tha Aux Fed Subs can help, but cause a lot of confusion if someone isn't up on how to run it, which is why I generally stay away. Also Proper array of speakers helps a lot, and understanding coverages. In general it's the same gig as a Proper sound reinforcement job mixing bands.
Todd A.