1. That's why they brought in the veterans they brought in. The biggest issue with the 3-4 transition is the linebackers, and with Thomas & Vrabel, that's half of the equation that already knows what to do.
2. They have just as much experience and inexperience as any other team out there.
3. TE's don't really factor into Haley's offense that much, and Cassel hadn't built any chemistry with Tony. Cottam is perfect for what they want out of the position. Bobby Engram should have a huge year for the Chiefs. Low YPC and not very exciting, but will be a key player in moving the chains.
4. Pioli looks to the long-term, but it's not like he's not trying to put together a team that can win now, either... His philosophy is as-much geared towards cheap, plug-in veteran free agentss who want to win through as it is the draft (probably more-so).
5. Overall, they're really not that young, especially when you consider how experienced the younger players are.