-If you mean 'hours going back' under spending times on Earth, prepareing for journeys, you may haven't red my suggestions abaut Jupiter, witch includes ( near this space dimension ) a good solar system, wich you explored once ( I mean building a base wich can recover rescoures from the planet ) you will just have to travel between planets for easily recoverable rescoures. For food, you would go to the Moon for cheese, you would jo to asteroids/moons for water and easily recoverable ores, the Jupiter for H2 fuel, the Earth for O2, and to Venus or Mercury for your thermal power plants. Going around a few times, and you would be ready for exploreing some new worlds!
-If you mean 'hours of going back' under long space travels for rescoures I tell: the rockets should be faster, as you see on the map, the same time should be made used for the tier1 rocket to go to moon, use the tier2 boosters for getting to Mars in the same time, and the Tier3 penta engines to speed to Jupiter, nearly during the same time (oh you haven't saw my tier3 rocket concept, but you will ).
It doesn't matter. If you want to play KSP, then go play KSP. Most of your images look like you took screenshots right out of KSP and changed a few things. The current system works perfectly. There's no need for this exploration of space crap.
I play battlefield. You don't see me making dumb suggestions to add armored tanks explore planets.