If we're counting Mars, Kamuro, Ryuga and Femme (Aka movie riders), then you're missing the following for Gaim:

Bujin Gaim (a Ryuga type)
Dark Gaim (another Ryuga type, this time even closer)
Shin Kurokage (not the same Driver, powers, or character)
Fifteen (Uses a Sengoku Driver).

PS Lapis is the character's name. The rider is named Kamuro.

I never wanted to count Bujin & Dark Gaims including Fifteen.