I've walked around some of the east side of Loch Lomond, but I haven't been up Conic Hill yet. Hopefully this year
If you're starting your hike early in the morning and find you have some time left I'd recommend visiting Inchcailloch Island! A little boat leaves from Balmaha boatyard (behind Oaktree Inn) and takes you across to the island, only a five minute sailing!
The skipper will drop you off and arrange a time with you to return. Two and a half hours should be enough time to explore the paths on the island, but if you really want to take your time allow a little more.
There are three different paths you can choose from to reach Port Bawn at the other side of the island:
Low path (1 mile) ~ a gentle woodland walk with a few slopes, passing the burial ground and farm ruins
Summit path (1 mile) ~ a more strenuous climb to the top of the island (85m) and enjoy the views
Central path (3/4 mile) ~ walk through the heart of the island and take in the oak woodland.
Each path takes around 30-45 minutes.
You do need to walk back to where you were dropped off though (North Jetty), so allow time for this.
Have a brilliant time in Scotland!