Going to sound weird, but I think that McGowan/Alvarez/Morrow's progression is far more important than Cecil's contributions. I have never really thought of Cecil as more than a really good 4th starter, where as McGowan/Morrow could easily slot into that #2/3 starter postion, if they reach their ceilings/regain form. I guess I just don't find Cecil's success that imperitive to the club's success - and that is taking nothing away from Cecil. He had a really good season, and until his drop in velocity, appeared to be on track to becoming a good #3.
I feel that kids like Hutchison, Jenkins, Drabek could all have solid seasons, and really help off set the loss of Cecil in a rotation - similar to what Alvarez did last year. The loss of Morrow or McGowan (if he regains his form), would be crippling to the franchise's hopes of a playoff birth.
EDIT - all personal opinion of course