I suggest a small change in the Solar Panel behavior: ability to have output spot.
If player use Wrench on Solar Panel, this side becomes output. Second use - dismount as usual.
If Solar Panel placed targeting non-EU block or was placed before, it has no selected output side. If placed targeting Cable/Machine/EU_storage - this side becomes "output".
If Solar Panel has no side marked as output, it behaves as now. If it has, EU it emitted to this side only.
If Solar Panel emit EU packet through the output side to the other Solar Panel, second Panel emit one EU packet only adding input EU to own EU generated.
This should greatly reduce number of EU packets on solar fields, discourage using of tin nets, allow solar fields to output higher voltage than 1 EU/packet.
I do not like "advanced" solars because in my opinion solar usage should cost surface space.