Hey emporilio,
If you’re tight on space – you can certainly setup an external enclosure for the Vue 3 device (and power supply for Flexible Sensors) and then run the wire-harness/sensor wires through some conduit. Works great for a lot of customers w/ cramped panel spacing, only caveat is that you’ll want to make sure your enclosure is watertight and weatherproof.
If deciding to skip the mains completely, totally fine as well. You won’t get your Net/Total measured but the “Total” displayed within the app will be the sum of your connected 50A CT measurements. In that way, if you’re able to capture everything w/ a 50A CT then your total there should be pretty much as accurate as if you were measuring directly w/ the 200A CT’s.
~Kevin