In reply to stevieb:
I wouldn't want to walk in to Ben Alder, no way! I have been up there twice and it's a long walk, especially with the last part being a bit boggy. You could cycle in from North, though. Tarf Hotel is awesome, but it's a rough walk-in with winter gear.
Allt Scheicheachan would be my vote. Easy walk-in and few Munros around.
Alternatively, I am going to throw in Coire Fionnoraich. Surely, it's a 1.5 hour (or 100 miles) longer drive, but the walk in is just over 30 minutes and if you are carrying loads of fuel, you might even save up time. There might be other options with shorter walk-ins, surely.