We've got a bunch of mylar sheeting that we can crank out easily enough. Wicker baskets can be woven together from reeds along the moat and the pond in the forest. Even some of the vines should be able to help hold things together.
WE could do the old "bon fire" heating for the ballons, or rig a methane or hydrogen burner for them. Or, I guess I could whip up a way to fill the balloons with something "lighter" than air like helium and just put a fairly tight sealing valve on them. Maybe even rig up an electromagnet for the bottom of the basket that would have enough pull to provide meaningful "ballast" to allow you to go all the way to the canopy, or bring you back to ground.
As for air currents, we get some interesting currents going in here due to temp variants, the O2 recirculation, and the vegetation. Gotta be more careful out towards the edges than right over the castle environs. Get's an almost Coriolis effect going where the canopy slopes towards the ground.
True. I think standard burners would be the right course. There's a certain mystique about a hot air balloon.
I'm suggesting a requirement that each balloon going up should have at least one certified dome technician, in case the balloon rises too high and gets tangled in superstructure or something.
It would be best if all pilots or fliers were trained in the dome maintenance safety procedures, but I won't insist on it.
The real challenge will be accuracy in navigation. We'll have to set up landing targets, and figure out some prizes to give.