I hate to be the voice of crunchy here, but I hope you've got killer stats.
Str: you're going to be optimized for melee combat, so you'd better be able to deal out damage; that requires a high str.
Dex: You won't have any armor on, so you'd better have a high dex to avoid being hit all the time.
Con: You'll be on the front line of combat, and you'll need all the hit points you can get, so you'd better have a high Con.
Int: Okay, if you don't mind having any skills to speak of, you don't need a high Int.
Wis: To a lesser degree your paladin abilities depend on Wis, and to a greater degree your monkish abilities depend on Wis, so you'd better have a high Wis.
Cha: A low-charisma paladin can't turn undead, can't lay on hands, and suffers from other handicaps, so you'd better have a high Cha.
This character is going to suffer if she doesn't have five above-average stats. Can you manage that?
If not, consider going for the cleric/monk, who needs four above-average stats, and who can also be a buttkicker for goodness. If you focus on clerical buffing spells, you can even make do with three or fewer high stats (compensating with bull's strength and endurance). I think you can have the same character concept, but drop the paladin's high charisma requirement.
Of course, if you can manage five high stats, booyah!
Daniel