Try a triangle of Glasgow to Glenforsa (Mull), Glenforsa to Plockton, and back.
Glenforsa is a lovely grass runway running parallel with the beach, with a very nice hotel a few minutes walk away. No fuel so far as I can recall.
Plockton is a pretty fishing village, decent tarmac runway, lots of places to eat or sleep in walking distance. I've picked up fuel there, although it was fairly pricey (mind you, the chap told me he had to trailer it from Inverness, so I forgave him that).
Glasgow - Mull is short but pretty along the mainland coast. Mull - Plockton is mostly over mountains, with a good view of Skye, a short en-route detour takes in Eilean Donan (the castle in all the films).
Broadford airfield on Skye is nice and just about in-sight of Plockton, but if you want to go into Broadford (which is worth it) it's a 4-mile walk and mobiles don't work, so book your taxi to meet you in advance if you aren't feeling energetic.
G