I also disagree with this 5-6 year window thing people keep mentioning. The rich get richer in baseball, but "rich" isn't always about money. If we can pick out the right players to sign long term while dealing other veterans for prospects, there is no reason that we can't keep plugging in talent to replace talent.
The Grienke trade looks like it made us a better team in the long run. If we can make similar moves like that when we have enough talent in the majors to compete, I like our long term prospects.