Get a couple of those folddy uppy things from the OS and look to the north of Glen Lyon between Bridge of Orchy and Pitlochry you should see loads of big hills and loads of different possible routes between them. No doubt someone will be along soon with a step by step route description but personally I'd rather make up my own.
Sorry I promised to stay in bed until October but I just could not resist this!

Sue and I walked from the Loch Lyon to Milton Eonan (excellent self catering cottage/ B&B)2010 when we were forced off our route by high winds. There isn't much alternative to the road until Gallin where I think Jean Turner walked through the grounds of Meggernie castle without problems ( we didn't try). As road walks go its quite a pleasant trundle. In 2002 I went up Stuc an Lochain from Pubil and down to Lochain an Daimh which cut most of it out and was relatively easy going.
From Bridge of Balgie to Invervar there is a good track south of the river - was our FWA but we didn't use it. According to my vetter it goes OK. Below that I think there is no alternative but to walk the road. It pretty narrow and twisty with a lot of blind bends so though not busy I wouldn't fancy it. You would though get to sample the delights of the hotel in Fortingall and see the famous yew tree.

I've hard good reports of dehydrated rack of lamb. How did the AGM go by way.

Me and one of my sprogs walked from Bridge of Orchy to Aberfeldy using Glen Lyon and we found the road at the Western end of the glen to be quiet and pleasant and after taking coffee and scones at the tea rooms, we used a track on the South side of the river at the Eastern end and camped beside the river next to a seat with a sign on it which said "no sitting". We took this to be sarcasm.

A long day at the NUT punctuated by speeches and lunch. I spoke to several motions, helped to save the reserved seat for Northern Ireland, spoke against secession from the FDA and failed to have the motion on planning for Scottish independence remitted until we have a bit more detail on what the proposals for Scottish independence actually look like.

Then I had dinner with my wife (who was ever so complimentary about how supportive Challenge Control had been when they temporarily mislaid me ... and rather less complimentary about the empathy skills of the Lochaber police, who tried to reassure her with comments such as "Oh I'm sure he'll be alright. It's terribly windy up here. We've had articulated lorries blown onto their sides, you know") saw her safely onto a train back to Bedford, and boarded the sleeper back to Spean Bridge.

Oh, and they refused to take an excess fare, even though my tikets were from and to Corrour, but I actually travelled from and to Spean Bridge ...

Very euphemistic.