Why does UR or UW seem silly to you? Red and White have first strike and double strike - the interaction with ninjutsu is insane. Check out my UW ninja deck:
Also, I don't think you're benefitting enough by adding Green here. The only difference is that you added 4 counterspells, and they are nice counterspells, but you could have found nice counterspells in just mono blue as well such as Cryptic Command. The evasion creatures are good too, but black has equally good evasion, so what's this deck but a UB deck calling itself UG?
Also, Distortion Strike seems a bit redundant for the deck. You have quite a bit of evasion already, and if you really want to connect with your opponent in Green, I'd suggest Trample...Overrun seems like a good finisher and damage connector for Ninjutsu to really shine.
4 Ornithopter
4 Silhana Ledgewalker
4 Jhessian Infiltrator
2 Mystic Snake
Ninjas:
4 Mistblade Shinobi
2 Walker of Secret Ways
4 Ninja of the Deep Hours
3 Higure, the Still Wind
4 Distortion Strike
4 Mana Leak
3 Peel From Reality
2 Voidslime
Lands:
3 Yavimaya Coast
3 Flooded Grove
9 Island
7 Forest
I've had a mono blue ninja deck for a long time now, and I think that the inclusion of another color really helps.
UR seems a little silly, as does UW, so I decided to do UG.
I tried UB, with the rats, but they weren't very impressive, on the whole, since Okiba-Gang Shinobi and Ink-Eyes, Servant of Oni were the only stellar ones.
I tried to work in crazy card advantage with Eternal Witness and Yavimaya Elder, but they're not sneaky enough to be worth it.
Suggestions are appreciated.
GR Shamans
B Vampires
UG Ninjas
The candles burn out for you; I am free.
http://forums.mtgsalvation.com/showthread.php?t=281107
Also, I don't think you're benefitting enough by adding Green here. The only difference is that you added 4 counterspells, and they are nice counterspells, but you could have found nice counterspells in just mono blue as well such as Cryptic Command. The evasion creatures are good too, but black has equally good evasion, so what's this deck but a UB deck calling itself UG?
Also, Distortion Strike seems a bit redundant for the deck. You have quite a bit of evasion already, and if you really want to connect with your opponent in Green, I'd suggest Trample...Overrun seems like a good finisher and damage connector for Ninjutsu to really shine.
R: Copypasta Sauce {Browbeat}
UR: Mana Cache , One Spell to Bind them All {Magnetic Theft}
UG: Epic Struggle , All-In-Poison {Metamorphosis}
UW: Planar Overlay , Decree of the Bailiff {Saprazzan Bailiff}
BG: Thought Gorger , Dark Chroma {Umbra Stalker}
UBR: Dwarven Shrine
WUBRG: Dissipation Field , Maelstrom Nexus
Faeries are also pretty good with ninja's, though not too casual friendly.