My bet: unless the RWS .50 feeding systyem problems are cured, and as recently as a month ago I was e-mailed by a Stryker crewman who says he thinks that's the worst bug in the system, you'll see the .50 or Mk 19 replaced with a pair of 7,62 M240Gs. Or even old M60 MGs, if there's a shortage of MGs for fitting to the vehicles.
One of the nice features of the now-cancelled Military Police 4-wheeled ASV was its ability to use both the .50 and the 40mm Mk 19 at the same time. Or should one jam or run empty, the gunner could flip his gun safe/selector switch, and resume immediately with the other gun. When Stryker's gun goes on strike, that's it.
I hope we see them sprout more grabs and handholds. But I fear that the composite armor may preclude obvious answers of that sort.
How's that for hand holds?