It seems like the complication going forward will be fuu deciding how he feels about rena vs the other 2 girls.
For fuu to fall for nino, it'll require something major. As it stands, he simply acknowledges her feelings. Minus the wildcard because we don't know if fuu has to make a leap, or if he's already heading down that path.
Basically, we know how far nino has left in the race for fuus heart, we know rena has a head start but itsuki is squandering it, but we don't know where miku is.
She could be last, she could be first. We'll find out soon enough.
If she's not ahead of rena OR nino, then I can't imagine miku will stay in the race more than a couple weeks