It is very hard for the player to make decisions when he can't really see what is hapenning, something as simple as a display of the trajectory based on present velocity could help a lot, or maybe hint the player for the X velocity required for his altitude !
I also tried to make a game about putting stuff into orbit in the past and it was painfull to see how unintuitive it seems to most players. Couldnt beat it without cheating ( i used this 🤫)
It was fun anyway, good job for a first jam !