i built my pathfinder inquisitor so that in-character, the team i played with forgot what my class was.

ooc, everyone knew i was your skill-monkey inquisitor that could stop-gap anything the party sucked at: healing, skills, recon, stealth, offense, socials, whatever the situation called for, i was good at it. not great, but more than adequate.

the only sign that the characters had that my inquisitor was not a swashbuckler/rogue/bard/ranger/dex-build fighter/evil genius was his holy symbol customized to be a badge of office. by session 3 they forgot and assumed i was your run of the mill pirate. the players forgot too despite me casting judgements every so often, casting healing spells, and being immune to alignment shifts.

now, here's how i pulled it off:

1: i waited to see the group's composition before deciding on being the generalist with the group's and the dm's approval.
2: i optimized that character to be as versatile as possible, thus not compromising group efficiency, and in a way, becoming a force multiplier.
3: i told the players what i played as, and that my theme was going to be the "undercover crimefighter", so no, i wasn't going to parade as my class often, and quite often would play against type to trick anyone we came across that i was your garden variety dex-build beatstick.
4: i roleplayed the hell out of it without keeping it secret. a teammate would ask ooc what my class was, i'd answer honestly. ingame, i'd answer "years of practice".

keeping your character sheet secret is skeezy in my book. too many munchkins, too many bad stories.
keeping your team out of the loop in character? rogue's gotta rogue, yo.
keeping your team out of the loop out of character? a necessary evil, and to be used as little as possible and in the direst circumstances. trust is a 2-way street.
keeping your class secret in and out of character? outlook cloudy for good fun. outlook good for trouble. warn your team what you're going for. i wouldn't jump into a game with a secretive character simply to know what build would be useful.

look at it this way for your teammates: wizard - rogue - ??? - fighter - you

do you play cleric to cater to healing? oh no! there's 2 healbots in the team!
do you play skillmonkey? a wild bard appears!
do you play support? aw, too bad, there's already a sorceror in there.
do you play dps? drat, both a ranger and a monk in the same group! now you're lacking magical support!
etc, etc...

just playing the odds of the role-filling, there are only so many possibilities before hitting redundancy. a bit of redundancy is good (that's why paladins have healing spells too). but 2 guys playing the same role? boring for one, both, or all concerned.

your character concept is novel, and i wouldn't mind playing with that kind of paladin. it's refreshing. but warn your team at the very least.