I find KAS very, very useful. It permits you to dock, or simply attach vessels or Kerbals using cables. You can retract/expand them to fit your needs and transfer fuel once plugged in. Also, MechJeb is useful for node planning, rendezvous and ascent autopilot, making easier, more precise and automatic, all the actions you want. If you have a second computer, (like a laptop) I recommend you Telemachus that enables a web interface, so you can send basic commands to the flight and get graphics of fuel, gravity, atmosphere density, get orbital informations and vessel informations... To enhance gameplay, I recommend using Kethane, Extraplanetary Launchpads (mining ore and drill fuel), ISA MapSat (terrain map of the planet - to find the best places to establish a base) & IonCross (Oxygen support - your kerbals die if they don't have anymore Oxygen). Take also a look at B9 parts, NovaPunch2 parts, Lazor Docking system (very very useful to dock). Search around YouTube also (Scott Manley's videos are awesome and very useful)!