Is SWTOR single player actually any good?
If you enjoyed KotOR 1+2... then I'm sure you'll find something fun in the class stories. Jedi Knight and Smuggler are the most fun on Rep side (Consular is kinda boring, but that might be because I play him 100% light), Bounty Hunter and Agent are the most fun on Imp side. The other classes have their moments, too. Sith Inquisitor gets to be sarcastic and snarky all the time, even to Grand Moffs and Darths. So far only my Trooper managed to get laid (Sergeant Jaxo is hot!), despite me flirting with everyone I can. Well, except for my Sith Inq, who just hates everyone. 
There are tons of references, there's a lot to do... in fact, it's kinda overwhelming at first.
It's obviously not quite as good as a single player game but it's entertaining enough.
I recommend to subscribe for a month though... f2p gameplay is nearly crippled and just gets in the way.