Ideal Round Britain yacht for singlehander...

[Leopold Bloom]

Pretty much any boat will do, it’s not difficult. I sailed a Moody Eclipse 33 around this year, mostly single handed. Don’t rush, places I thought would be interesting weren’t and vice versa. Highlights were: Chatham, Wells next the sea, Hartlepool, Whitehills, Caledonian Canal, Ardglass. Not so good: Blackwater and Colne, Lowestoft and Crinan. Scotland is great ������

 

[Daydream believer]

Don't go through the canal -

Not quite sure how you can advise one not to advise someone not to go through the canal when one has not actually tried it. No more than I would advise someone not to go round the top.
Having a boat with a self tacking jib & all lines in the cockpit if single handed really is a boon & i would agree with you on that ( being a Hanse 311 sailor but there are others with ST jibs)
I also think that a boat with decent performance is less tiring. I sailed in company with a Vancouver 36 on one leg of 60 miles & F 6 but got fed up going back for him so after 20 miles I had to leave him behind. Arriving 2 hours before meant I could get bedded down, out of the rough stuff & rested much earlier.