I’ll copy my reply from the same question on UKC for the non- rock climbing cyclists…
The Keswick area passes are great as you can choose how far and steep you want and make a route accordingly. I would rank them from hardest to easiest as :
Honister from Buttermere
Honister from Borrowdale
Newlands from Buttermere
Newlands from Braithwaite
Whinlatter from Lorton
Whinlatter from Braithwaite
You can do them all in a long ride without repeating any, or choose a combo to suit.
Fred Whitton is a great day out, don’t underestimate the hilly bits that aren’t major passes, especially Cold fell area.