Ill keep it short and simple
1- for your character hold off on leveling up until you get to jedi enclave on dantooine, and become a jedi (looking at when this was posted that ship might have said but oh well)
2- i'd invest at least a little into persuade when you level up with your main, the other skill which i'd say is essential is treat injury
(PRO TIP: you can heal by opening your item menu inventory and just clicking use item on any med kits, this will completely skip any animations, meaning you can do it DURING your attack)
3- you'll want at least one of the following force powers for the final boss battle (you'll see why) at least if you wanna make things easier, if not then you can just slog it out
Choke, kill, lightning, storm, throw lightsaber, force breach, disable droid, destroy droid, drain life or death field
I only say this because during my first lightside playthrough i somehow managed to not pick any of those and as a result it felt dissatisfying
Oh and TALK TO YOUR COMPANIONS look for new dialog as much as possible, most of them have side quests and more