A combo isn't any easier to lug around than a head and bottom. Espceially these days with all the micro heads available. My Carvin BX500 weighs 4 lbs and fits in my napsack. It's much easier for me to wheel a Bergantino 610 behind me with the carvin in my shoulder bag, than it was to carry a 30 lb gk in my hand, or to strap that gk onto a luggage carrier.
I also have a Bergantino NV610 - and a 37 pound 1x10 combo (the Promethean P5110). For me, anyway, there is no way it is easier to get around with my gig bag, micro head and 610 then it is to get around with my gig bag and Promethean combo. The carrying case for my Promethean has a shoulder strap. Depending on the situation, I put on the gig bag as a backpack and carry the combo on its shoulder strap, or I carry the gig bag in one hand or on one shoulder and put the combo shoulder strap on my other shoulder. WAY easier than, for example, trying to drag my 610 across a gravel parking lot to get into where I'm playing. Much less up any stairs.
And, the Promethean has all the advantages your mentioned in terms of having a separate micro head and cab, because the head detaches for use by itself. When the 1x10 combo is way too small, I can just pull the head off it, put it in its own carry bag (or a gig bag pocket) and then take just the 610, if I want to.
Sure, if the OP is never going to want/need a smaller cab than a 410 or 610, then it could make sense to just get a micro head and a 410 or 610. But, seriously, who NEVER wants/needs a cab smaller than a 410 or 610? I'm sure there are some that don't. But, based on the OP, she is not one of those.