If you're willing to take a swordsage level to get the prerequisite manuevers, it could be worth your while to consider Shadow Sun Ninja. It's especially nice because it would allow you to take some of the nicer Shadow Hand/Setting Sun maneuvers like Shadow Blink (which has no prerequisites. :D ), or Fool's Strike as Crusader maneuvers, and progress monk class features as well.

I would really recommend another look at Master of Nine as a monk/crusader. With +5 maneuvers readied on your Crusader progression, it means you would start every battle with 7 of 10 maneuvers granted, which can be very handy. As a bonus, ToB prestige class level advance your initiator levels in all your martial adept classes, so multiclassing with them can be extremely beneficial.