When we considered, many years ago, to participate the "Google Lunar X Prize" competition, our envisioned system was a giant, torus-shaped stratosphere balloon that would have a small rocket-launching system in its small open middle. To be able to have control over its position, our concept also had a number of propellers along the "equatorial" line of the giant torus-shaped balloon. The outside would have been very dark, to take advantage of using sun emissions to additionally heating up the gas inside the immense balloon, as this would aide in the rising of the balloon.
The idea was to bring the rocket launch system to an altitude where the atmosphere would be thin enough to minimize vibrations of the rockets during their start phase, thus allowing for reduced material strength of those rockets, meaning less material being used, meaning less start weight. Also, meaning a lower amount of fuel as the rockets are launched from a much higher altitude which again results in less start weight.
With our concept at that time, we focused on relatively small rockets, meant to target the market for micro and small satellites only.
If we had continued with our project, the strato launch balloon would have been inflated and launched along the coast, risen over the open, empty ocean towards the stratosphere, and launch the rocket from there.
If you want, you can try with an online search if you can still find any traces of our project on the Internet, but it was way back, in 2009. Not sure if any "left-overs" can still be found...
Our project name was:
MOON RUNNINGS Jamaica
(everyone knows the movie and history of "Cool Runnings") :-D
It would be nice, if your JUNO game could incorporate parts for such a stratosphere-based balloon launch system for rockets.