If the purpose is gaining mixing control by using one pair of mics for up close direct sound and a second pair for ambient room sound, you want to reduce the amount of direct band sound in the room mics and the room sound in the direct mics. You can then blend them to get a good balance, otherwise if you have direct sound in both it limits the control you gain over that direct/reverberant balance.
Your close mics (the X/Y mics in the Zoom placed close to the source) are synonomous with a dry soundboard feed, the room mics provide the sense of space, ambience, and crowd reaction.
In that case, omnis can be a good choice for an ambient room pair. Spaced omnis are one of the best configurations for recording an ambient enviroment with a nice sense of space. I sometimes put them below the stagelip facing the audience so that the stage is blocking the direct sound coming from the band on stage but the sound of the room and audience is clear.
You can mix two pairs both of which were setup to get a decently balanced sound on their own, but that offers far less balance control and more potential interaction problems. It may sound good or it may not, but two sepearate pairs run that way are usually more valuable for comparison between the two or simply for redundancy in case one pair has a problem.