SK is best choice especially for solo and party exp. You have solo dps, you can pull trains in party. Class is very strong on pvp and usefull in almost every aspect of game.
SE is good class but kinda out of meta right now so its pretty hard to find cp. It cant rly exp solo efectively and about party exp im pretty sure you can find party but not as easily as with sk
Paladin is out of meta pick, i would say the worst out of these 3.
I recomend Sk by far over other 2.