Yes, it is a strong build, and it can be even stronger than you think if you learn how to use it correctly. Sub cleric or sub warlock are another options too, they are all different, but all of them are very strong if used correctly.
Just make sure that your connection doesn't have much delay to joymax if you plan on going for warrior/rogue, because if it has, you'll have a hard time switching weapons during pvp fights, because you'll need to change them very fast and a delay would make it way harder, and thus your effectiveness would be greatly reduced.