Having only Kolb will be a struggle for you in the saves category.
You IF is actually quite good as long as Mauer stays healthy and Delgado comes back the way most expect he will. Your OF is also pretty good although Bay just hurt his wrist/hand today? Good amount of speed in the OF and with Morno, Aram, delgotit, lee, and bay you should be allright in the power cats as well.
Starters look good with an excellent 1-2 in prior and mulder as long as they can both bounce back.
The more I look at it the more it looks like you have alot of high risk players. (Smoltz, Mauer, Arroyo, Mulder to some extent, Aram, Bay, Morneau. In my opinion I feel you will be allright. Your players are young but I am high on pretty much all of them. However, it may be worthwhile to trade for a little more stability just in case.