ploxus

Does MechJeb take advantage of reaction wheels? I noticed MJ doesn't enable SAS when in auto-pilot. Or do reaction wheels work without SAS enabled?

One thing I thought about reading your reply. I think you'll end up in a backwards orbit in Laythe - so technically you're doing a gravity assist + aerobrake. That could complicate getting to Tylo in that you'll waste some dv along the way. But all in all lots of things are possible in the Jool system. I could spend all day just dancing around the moons and flinging myself places.

I just started playing around in the Jool system this weekend so I'm definitely not an expert on getting to it's moons. But by far the most efficient way I've found to get in a stable orbit is to get a good equatorial trajectory from your transfer orbit, aerobrake around Jool at 119km, which should line you up to make an encounter with Laythe(or close to it), then aerobrake around Laythe at ~25km. Doing this should only cost you about 50 m/s of adjustments on top of your transfer burn. The key is having a good trajectory from your transfer orbit.

I think it will/could add great tension and complexity to your missions. 'Don't screw up this landing Jeb, we can't afford to send a rescue'. It could be an opportunity to add a lot of realism too. Let's say you want to send an unmanned rover to Duna. First you'd need to set up a network of communication satellites around Kerbin and around Duna, otherwise you wouldn't be able to control your rover. If you don't set up the satellites in proper orbits you'd have dark spots on Duna depending on the time. This would be a good reason to have things geosynchronous orbits, etc.