Silly question: It sounds like you're wanting more power... why not just get one powerful amp, instead of trying to daisy-chain some Elves? Then you have two different flavors on hand to fit whatever situation comes your way... rather than trying to band-aid a tiny rig for bigger gigs.
Not looking to daisy chain, was mulling over backups of similar configuration/output power/output resistance in case I needed a quick swap. 200w is the sweet spot for my gigs (when I have them again...).
And, yes, two ELFs should be two ELVEs!!