One other option would be LD-013 The Old Man of Coniston. 8 Points Quite a lot of tourist / water activites in the Village (Victoria Steamboat https://www.nationaltrust.org.uk/steam-yacht-gondola… ) and the shortest route starts in the village. Probably about an 8Km ( 5 mile walk return) but quite a lot of climbing (750m 2400ft) Paths usually dead easy to follow but maps and compass / GPS still needed! I have probably climbed it about a dozen times - all in my pre-sota days and it ( In my opinion ) is a nicer climb than the slog up Skiddaw!
Good Luck - and I hope the Weather stays as good as it has been today ( 80f…and Sunny )
Blencatha LD-008 again a nice walk, but the best start point is a layby on the A66 which probably isn’t a very good place to spend a few hours. Only climbed Grassmoor (LD-009) a couple of times and ( in my opinion ) it is a less interesting climb and again has a less interesting start point!
Final suggestion - Fairfield LD-007. By starting at Rydal the car would be parked next to Wordsworths Cottage and only a mile from Ambleside which has lots of touristy things. Slightly bigger climb and there are a few ups and downs and slightly longer distance (12Km return ). Ambleside is a bit nearer the middle of the Lake District and might suit better :-). Would much prefer to be walking rather than running a course but I’m not sure my employer would have the same view…
( I would personally go for the Coniston option as the hill is good, village is quite nice and depending on the teenagers there are canoes / boats on the lake. Sorry no castles that I know of… )