I think you have the basic idea right, now you just have to get your shading right.
1) The idea that the light has to be the same color as the lit areas is a myth. This is one way to do OSL but it isn\'t the only way. What you are doing here works just fine.
2) Shading her dark side more will work nicely to bring out the effect. Often, I have used OSL as the only light on a mini and left the dark side extremely dark. This should make it pop a little more
3) On a similar note, I think the mini needs black lining to make its own details pop. I think this is the source of your problems, moreso than the OSL. With the anime style of this mini (and everything else from the AT range) I think some black lines make it stand out a lot more.
4) I actually think that something that is hurting the composition is the amount of the spear that is at its lightest. In the picture, most of the spear is lit at its brightest, while you have more of a gradation going all the way up. I think that you have placed your Lighting based on this larger lit area, so you need to light the whole area before he\'ll look just right.
I hope I\'ve been helpful. You are doing a really good job, the mini just needs one small something to make it really stand out.