In reply to pillar:
Custs on Great End (beware avalanches)
Left and right parallel gullies Brown Cove Crags (at the far end of the buttresses from the Helvellyn path)
Several grade Is in Red Tarn and Nethermost Coves (beware cornices)
South gully left of Bowfell Buttress (climbers traverse from the Band can be awkward for the inexperienced in icy conditions, best approached from Mickleden below)
Lords Rake Scafell (beware rockfall)
Every one of these makes a great solo with few technical difficulties to overcome, but each (see parentheses) can offer up one or other of the special challenges of the winter environment. Enjoy safely.