Not to crush any feelings but I want to give you as much advice as I can so this is going to be long and please don't think any of this is me picking on you:
When painting always opt for thin coats over thick ones. It's better to have to paint several layers than accidently obscure details with one that is too thick.
I usually opt for about 3 colors when painting anything (4 if you count washes): a base color, a mid color and a highlight color. Your base color basically forms the shadows of the area, your mid color is the primary color you want something to be, and the highlight is only applied to the highest parts of the area.
Once you have your base layer down over the entire area you want to be a certain color (often referred to "blocking" in the colors) then move on to your next color, which should be a slightly lighter color. This gets painted everywhere but the recesses that you want to leave dark.
If you can paint each thin layer on slightly smaller and smaller areas, this will help create a more gradual blending affect more easily than trying to wet blend. Last apply your highlight color, also in thin layers, working over the higher points on the model, such as the edge of a surface that is pointed towards your imaginary light source (which is often straight above the model for most people as that is where most lights are in rooms so it makes it look more natural on the table) and any folds that'd catch the light (like the ones on his pants).
Now there are two ways to incorporate washes into the mix when doing this. The first is by painting the base color, using a wash, and then, when dry, repainting the base color over everywhere but the recesses. The other way, which is great for making things look dirtier or dingier is to use the wash last, after you've done all the highlights. This will darken the colors usually and blend the transitions a little better. This will also darken the overall fabric and get give it a bit of a dirtier or dingier look depending on the colors used.
I looks like you have blocking down pretty well (though always remember thinner is better when it comes to paints. It shouldn't look like coloured water, but it should be thinner than it comes out of the bottle. Generally the ratio is such to give it the same sort of thickness/viscosity of milk if that makes any sense), you just need to add some more layers to really get it looking good.
Now you don't need to get too complicated (like I'm prone to doing) and end up with 30 different paint pots on your desk because you obsessively pick out different details in different colors, but definitely try and come up with a system (like grouping the colors you need for certain things together, and then working through several models at a time so that way when the first layer is dry on the first model you're finishing the last and you can go back to the first one again. I find about 5 models to be optimal for me when batch painting like that, but some like more than that, some less, it's all what works for you) to make things easier to paint overall and things will go swimmingly for you.
While I'm at it, here are a couple winter camo schemes from real life to give you some ideas of how the military (several of them) do the whole winter thing:
Now for sanity (as well as to prevent hand cramping) if you want to do a the camo thing I'd probably go with the more detailed camo on the sections of armour on the arms, shoulders and chest, and then do a white fabric (which is basically a light gray working up to a bright white) for the fabric parts like his pants and sleeves.
That or go for the full Space Wolves color scheme as they have a nice cool (as in color temp) color scheme that'd be pretty easy to replicate.