Sure, though Rogue hated Dazzler for a while but presumably there isn't a problem with them dating the same guy. So Felicia working it out with Peter isn't too much of a stretch if you wanted it. Work the "two people trying to be better" angle.
But if the Writers decide to have that scenario play out with Felicia and Null so be it. It's a fine enough pairing due to Felicia's love of excitement and Null's ability to find it.
Besides, if you guys rule on the 50% where the girls don't know he's Spidey, he has other things to be worrying about then a noisy cat.

Not maintaining trust in a poly relationship? Tsk tsk Mr Parker.

The way that drama would play out is very on brand, "Well I was honest about my personal life with you girls, just not...you know..."