EMC rejection may be an issue, I have solar panels on my roof. That may add to the problems of an eaves mounted loop (though I will follow up with Ed’s comments).
I think I have abandoned the vertical idea.
That leaves the windom, doublet and off-centre fed dipole to investigate.
At the moment I don’t have any equipment capable of generating more than 200W, but didn’t want to be limited.
Thank you all for your thoughts so far