Ultimately, 'X' level of protection for 'X' individuals, 'X' level of electrickery/connectivity, covered personal kit (rather than festooning the outside of the vehicle), a big enough powertrain to drag the whole lot around with appropriate sprightliness, climate control, range/external tanks and so on are going to dictate a certain size no matter what.
How that squares up with 'Can you drive it down this country lane/forestry track, or across this bridge/marginal terrain?' I guess has to be seen.
Typical vehicles are definitely over armed these days, one of the Boxers that was being shown off had 2 ATGM, 30mm main, 7.62 Coax, .50 RWS and that doesn't include the 5.56 Rifles, 40mm UGL, 7.62 MG and misc handheld AT weapons that the troops have. Stress test of logistics for that would be interesting.
There is also a interesting trend of fitting an RWS on top of an RWS turret, is that really necessary??!!