Hey Chris
I really don’t like these model names for Enphase, I think they should be more descriptive, or at least more distinct. Anyway, that aside, look I think you would be fine to use iq7+ with the 360W panels. Oversizing is perfectly normal and often desirable, you can see details of that in the Guide. The standard is mentioned in the Enphase spec sheet so I imagine they anticipate this. I am 98.5% confident that there is no warranty issue with that either, but you might want to check with Enphase to be 100% sure. Having said that, this throws me a little “2. Maximum DC input limited to 350 W at 25oC as per AU/NZS 5033:2014 4.3.12(d).” Hopefully someone more familiar with Enphase installs will help us out.
The advantage of going the + instead of X is that you can maximise that 5kW inverter limit. More info on oversizing your inverter.
Cheers
Marty