I've had great fun with my paladin. The basic concept was to be really angelic and 'too good for this world', so edging towards NG rather than LG. Gets sad when other characters are somewhat disreputable but attempts to strive to be an example to others, and not an overbearing boor like the stereotypical awful good paladin. I think personally if you do play an overbearing boor you're probably not doing justice to your stats, given how paladins generally have massive charisma. They should generally be likeable and well thought of, not a cross for the party to bear, IMHO.
"It was me that swore the oath, not you" is the usual comment when someone is talking about poison or something dishonourable. (The others arent evil but there are a couple of neutrals who are hardly paladinly). On the other hand she's really generous, selfless, brave, etcetera. It seems to work too, other party members help people out for free these days, she's considered the party leader even though she's humble and saying she's not worthy of such accolades, etcetera. Still lawful though, always nice to the city watch, was organising contracts and stuff when someone wanted to just steal someones house (she made them talk to the city watch and get a proper contract of ownership), and almost ridiculously, naively good.
I think a smite bot is a bit lame and one dimensional, not to mention stereotypical, but you can play a lot more than that. If you look at Arthurian knights there are all manner of personalities there, from Gawain the lout to Galahad the saintly.