Great feedback! This was actually planned, but we ran out of time. My favourite ideas we haven't implement include:
- Progression missions with visual targets and rewards
- Milestones/achievements for distance and height records, including post-space goals
- A contract system, allowing the player to accept package delivery missions
- Fuel and engine upgrades for the rocket (and maybe more customization options)
It's reassuring that I'm not the only one who thinks milestones are a good idea!