So good! I was skeptical about the gameplay when I used to watch videos of this game but it works really well.
You have 20 levels to rank up jedi powers, combat skills and feats (your starting class determines which of these 3 categories gets the most points per level up). A jedi power available is force lightning, a combat skill is something like flurry which increases your number of attacks but they deal less damage and might not hit and a feat is which type of armour you can wear or other passive benefits.
Combat is played on a turn-based dice roll system which might sound off-putting but works out well. Throughout the game you will meet characters who join you on your spaceship and you may choose 2 of them to accompany you outside of the ship. Companions will have their own stats, gear and skills so you can play around this (if you come across a companion with high lockpicking you might choose not to level your own and swap to this companion to unlock things for you). You can choose to level up your companions skills manually or automatically.
You can choose preset combat manoeuvres for yourself and companions such as ranged attacking or jedi support (buffs and heals) or you can choose to manually decide you and your parties actions by pausing the combat and assign attacks and items to a queue. You also don't have to use companions at all, you can elect to play in a solo mode where all the exp gained from enemies will go straight to your character. You also don't have to worry about this mode because companions will automatically be boosted to your level if you haven't used them.
How you play the game is up to you. I went for a dual-lightsaber character with light armour and attack bonus jedi powers but you can play as a sniper, explosives expert, jedi caster or even unarmed fighting.
The story is really what made the experience for me however. You will travel to multiple planets, gain your own starship, meet interesting characters and get to interact with almost every NPC you come across with multiple lines of dialogue and character development.
One downside to this game is that you can't play in a widescreen resolution without using mods (although guides can be found for this on the forums here on steam, along with HD mods and many others).