I enjoyed a run through the Trossachs yesterday and as a Morgan driving roads they would seem hard to beat IF you enjoy twists and turns on a tree lined route that occasionally opens out to present scenes Lochs hills and Glens. That being the case might be worth searching out "The Dukes Pass" which is my favoured and somewhat testing local(ish) road. Perhaps best to watch out for ...err..tourists not paying attention to the road .... laugh2

There is also a boat trip while along the length of Loch Katrine that may be of interest.
https://www.qwant.com/?client=mobile-app&q=steam+powered+sir+walter+scott+loch+katrine&t=web
all of which is not too far from Falkirk. You will find plenty of info both here and on the WWW much of which may not be accurate in these Covid times. I suspect those who live here may be best to provide day to day info, as so much may have changed in so many areas with so many folk forced to holiday at home...?

https://www.visitscotland.com/see-do/landscapes-nature/national-parks-gardens/loch-lomond-trossachs/

Yesterday was a local big city Monday holiday and yet the Trossachs roads were not crowded which made for an enjoyable drive, lochside parking spots were busy, but I was out for driving pleasure and not for spending time sitting lochside looking at the view and taking in the sun.

The WEATHER can control your day to day enjoyment more than much else and in the West of Scotland to be prepared for anything would seem key.

Also Some have visited and never seen a midge, but perhaps best to be prepared..?

https://www.calltoadventure.uk/post/midges-in-scotland

Hope you have a great trip though too much planning can create it`s own pressures by setting deadlines to be here, there or wherever, perhaps picking some different areas to explore from a central point might work out moving that central point every few days or so...

Whatever you decide, I hope you enjoy your stay.