Hi John

Sorry for the late reply, I’ve been away.

What you’re basically talking about here is similar to an East/West split installation.

Different orientations should be separate or a multi-string, but you’d get a much better yield from two inverters.

That said, with PV you’ll get more by putting it all on the West side of the property and without the cost of two inverters. The afternoon sun is generally brighter than the morning sun, so West works better than East.

Regarding the other questions, I must declare, I’m not a technical installer, just an enthusiast, so you can find good technical advice here:

https://www.electriciansforums.co.uk/threads/east-west-split-how-many-invertors.30833/