This sounds ok, but I dunno if I wanna stay for the whole weekend. Maybe Ill pop up for a day or something. Loch Lomond is quite a good place to go, plenty of private places around the edge of the water and the scenery is really rather beautiful. One thing I would say is that it would probably be better to go later rather than sooner. 1) Itll be more crowded 2) the midges are terrible until about september/october, and theres usually still plenty of sun to go round.
Another suggestion Id like to fire across your port-bow is that of the Isle of Arran. I know it has plenty of places to stay, including, but not limited to, amazing camping spots. Has even better scenery than Loch Lomond tbh.
Maybe itd be better if you all just came round to my bit.