@Lefty
Very true re the prices of used Pen F's - I've been doing a little snooping about and values are rock hard. They didn't sell that many (c/w the OM-D models) but as word started getting round what a great little camera it is, Olympus discontinued it. Those who've got them are either holding on to them, or selling in the knowledge the F is a rare beast now with the associated high price. MPB have one in at over 600 quid which doesn't look in its first flush of youth.
Ah.... that explains it. Makes it a tougher decision in that case. Also thanks for the feedback @miktec - much appreciated.
I actually spent today considering another wildcard, a Nikon Z50. Available in 'Like New' condition from MPB together with the pancake 16-50 Nikon Z DX zoom lens for around £670. Hardly pocketable, but much smaller than you'd think (it weighs less than 400g and is smaller than a Fuji X-T1/2/3/4 and is great value for money. Reading this blog about it from a friend and excellent landscape photographer Mike Prince is what turned me on to it. COuld still be an option, but then I'd have to buy a small bag for it, which contravenes my criteria. Food for thought...
https://www.mikeprince.org/blog/nikon-z50-review
Lefty