I think your team will go essentially as Mendenhall goes. If he can return to his pre-injury form, you're looking great, especially for a 12 team league. However, RB is probably still an area of concern for you. Charles is great, but for me Mendenhall and Bradshaw are question marks right now. If they're healthy (Charles for that matter, too), they will compliment your receivers very nicely.
Ryan is great at QB and Jones, Colston and Jackson could be dynamic. I'd hope for an injury free year and you could certainly compete in your league. Very nice looking team, now let's just pray the injury bug stays away.