Perhaps we limit recon and scouting in hot zones to Strykers...separating those tasks from general purpose errands and such for existing HMMVW's.
Sounds good to me – and I think that is existing doctrine. The problem is that local commanders have to do their assigned tasking with available equipment.
One of the problems I have with the HMMVWs is with being closed in. Even with bullet resistant glass the trooper is still looking out a window and isolated from his environment. It is nice to have airconditioning in a hot area, but at what price? There is also the nearly unavoidable psychology of being in a “safe” vehicle and protected from harm. Just as people who drive on our Interstates here at home in a car with air bags all around, impact absorbing frames and bodies, built in roll bars and low deductible insurance are usually not as careful while driving because much the danger has been removed, the soldier in an uparmored vehicle will feel “safe” and not be as aware. And of course, the ability to bail quickly out when necessary has been subjugated to this “safety”.
I saw some of the same reaction in Viet Nam when we would transport combat arms troops on our boats. They were all a bit nervous because they could not dig a nice hole in a steel deck. They could not quickly move to a safer area when under fire. All they could do was stay where they were – on our boat – and take it.
"There is also the nearly unavoidable psychology of being in a “safe” vehicle and protected from harm. Just as people who drive on our Interstates here at home in a car with air bags all around, impact absorbing frames and bodies, built in roll bars and low deductible insurance are usually not as careful while driving because much the danger has been removed, the soldier in an uparmored vehicle will feel “safe” and not be as aware." 
That's very true and very real...but...combat fatigue and road weariness impacts even the otherwise alert motorcycle rider after enough miles.
Which is to say, you can only be alert for so long. When you are alert, or capable of being alert, then being able to bail out has high value. For longer duty, however, you'd better have some small-arms armor protection. You can't forever remain so alert as to avoid getting shot, after all. For the long-term, you need armor.
Understanding the above, it makes sense that hyper-alert Special Forces put a premium on mobility rather than on armor for their hit-hard, hit-fast missions.
But longer-term SOF (e.g. a 2 week sniper mission) will use the armor of camoflage...an option frequently not available to GI's riding on a road in a GP vehicle (hence, the need for some armor).
There is a place for max mobility, minimum armor. There is a place for maximum armor. And most other places require varying degrees of compromises...keeping in mind that historically our casualties have declined as our armor has increased (because people can't be alert 24/7).