1) If you run out of electrical power, you can EVA out and use the RCS in your suit to nudge the craft towards the light (assuming you have some of those always-out solar panels plastered somewhere). 2) When you start migrating to deeper portions of space, consider using staging on your fuel tanks too. You'll save fuel in the long run using two half tanks and a decoupler instead of a full length tank. 3) This may seem like a no-brainer to most, but when designing a craft that's going to dock/RCS, configure the ship in the configuration it will be when you're docking/RCS (disconnect any staging that will be absent, etc) and then turn on center of mass. Use that to precisely place your RCS thrusters. RCS placed at exactly the CoM or equidistant from it will translate better in space and reduce the occurance of rotation when using RCS. 4) Use the Alarm clock mod, especailly if you run concurrent missions as it can track multiple ship's activities and notifiy you accordingly. Definitely use it every time you're making an SOI change and you're feeling impatient. Warping through an SOI change can drastically affect your approach distance to the new object, but the alram clock can pull you out of warp a few seconds before it happens so your periapsis is consistent with what you see before the SOI change..