Without any great depth of thought or reflection, the few that jumped into my head:

1) Vehicles are a means to an end, and should not become the end itself. There is a time and place for vehicle-based patrolling, but I am willing to bet that there is a proportionally greater need for dismounted patrolling in any type of operation. If we spend more time, effort and focus, both at the tactical/planning level and at the capability level (MRAPs?) on issues of vehicle platforms we need to do a reality check.

2) Tactical lethality at the section/squad level matters. Our sections/squads should be able to finish a fight, not just suppress. Artillery is nice, air support is nicer still, but we shouldn't have to rely on it to win an engagement. Sections and squads need to be able to do more than just suppress with small arms, they need to be able to fire and manoeuvre to win. I think the USMC has taken a step in the right direction with the IAR and the Brit Army an even better step with their 7.62mm DMW in putting a precise, powerful rifle at the lowest tactical level. I'm interested as to what the XM25 offers, too (despite my initial cynicism around such a heavy, power and tech intensive weapon).

3) Speaking the local language is very, very important. I don't think this is COIN specific, as I'm pretty sure the ability to talk with, gain info from and quickly direct locals would be equally important in a Cold War German battlefield, for example.

4) Campaign planning is essential. Killcullen's 28 principles of COIN does not equate to a campaign plan, despite the widespread interpretation of FM 3-24 in many military minds. Being able to drag an end-state out of anyone, at any time, that relates to the real world (and not a powerpoint matrix as is all too often the case) is the starting point for assessing whether a campaign plan exists.

5) Leadership is still about people. Powerpoint can't replace an orders group, an inspection or a CO's/OC's/Pl Comd's hour with soldiers.