What sort of walking? Do you want busy or quiet? - nearby town / pubs etc........?
I love Skye, Glen Coe, Fort William for Ben Nevis etc. or around Loch Lomond. I'd really like to base at Ullapool and do some walking around there too, Arran is on my shortlist as well.
Sligachan bunkhouse on Skye is good - you don't get the campsite midges, quiet though - only one pub / hotel and that's it.