Not really worried, the coaches will get it figured out, even if they have to take a starter or 2 and put them on ST, they will do whatever it takes to get the ST's shored up.
One thing I noticed against Ball St. was that we did kick at least 2 kickoffs through or deep into the end zone. It made me wonder why we cant do that with the majority of our kick-offs.
I do remember Jon posting last off-season that kicking deep on kick -offs so the D can take the field at the 20 would be important this year. Thus far in the season it looks like our kickers aren't getting enough air under the ball, so even if it ends up at the goal-line it hasn't been in the air very long, giving the returner a much better chance of reading initial blocks and getting through the first wave of defenders.
We will be fine on ST's. Our kickers (excluding Donohue) need to step up, and they will.