Legosats launch from helium balloons. They can rise to a maximum ceiling of the density of the craft/atmosphere. At that point the legosat should store the helium to be used as thrust. Fill much he and use ionizer to provide thrust. Use a exectable chemical engine for the initial thrusting. Saving your he for fine stationkeep. Then it should detach from the balloon. Immediatly drop away from the balloon and its legosat attachments. (These will be different in every system and launch so be weary of that balloon). In order to move Legoman Balloonist from 33km to 300+km LEO, you would need thrust. You need to use the Hohmann Transfer to attain the new orbit. Then stationkeeping. To go to GSO is a whole different Legoman. Start small.
Legoman systems should allow many excellent detection deviced;video, temp, magetic, radiowaves with extending antenna. Many excellent systems can provide supurb monitoring. Like a firesat system. Looking for forest fires.