Kerbin System Transport Advice Needed and atomic engine question

[EliasDanger]

So I'm trying to design a tug that can take all sized objects from kerbin to mun and back for refueling. It will stay in space. I have a LKO space station right now, and contracts to build one in mun orbit and minmus orbit. Thus tug will need to be able to haul those out to the moon and back to refuel at the space station. It will also be used to move landers and such around.

Anyone have any designs they'd like to share? I have recently unlocked the atomic engine...but while it does have a higher ISP than any of the chemical engines, but much lower TWR...so I have to use more of them...plus one atomic engine weighs a grip more than one poodle....but you save weight on oxidizer....but youre also going to need to add thermal control....so the question is what's best practically for my goals, and also a question about how best to use the atomic engines.

Edited October 7, 2015 by EliasDanger

[Slam_Jones]

If you're staying out of the atmosphere, LV-N's are the best way to go. TWR doesn't matter nearly as much in space (unless it's ridiculously low... like so low you couldn't possibly make a burn in time before leaving the SOI)

[EliasDanger]

Thanks for the quick response, guys! I shall move forward with a nuke design with confidence.