Good updates
I think this Pompeius Roma could be far more defensive, tended to stabilize the frontiers, more than enlarge them.
I am thinking in Germania basically, I think in this scenario we have not campaigns in Germania, a consolidation of the Rhine limes yes, but not an attempt to create Germania Magna.
It could be like something similar to Augustus principate, but there will important differences, principally I dont see this becoming like hereditary emperors of OTL, the Senate will remain more important than in OTL.
IMCO not to conquer Magna Germania NOW while Rome has the strength and will to do so will result in the same sort of "Migration Era" problems as in OTL.
Get them in the Empire now and they'll give the Empire the shot-in-the-arm it needed but didn't get in the 4-5th centuries OTL.
HoC