There no such things like "universal best of all kamae". Sometimes your body/feet position must be aligned, sometimes must be square with parallel feet. All depends of the goal that you want to achieve. Paying too much attention to the external form may result that you will not develop any content.
As far as kicking somebody that has square kamae, this is very risky activity. We use to establish square kamae as an ‘easy target' as an ambush for those naïve minds who will commit to an attack. It is enough to turn hips in the moment of the contact to smash them down to unify with tatami, really no effort LOL
All I can say if you think you can stand in a square posture at close range with an experienced kicker I think you a either1.very good indeed 2.The kickers are poor in relation to the mae geri.
I have seen /experienced guys who can apply kicks that are fast and powerful.Certainly I would not put myself in a position like you describe.Guys who know how to kick are in my mind hardly naive minds.Any kick /punch at close range is potentially dangerous.To think otherwise is foolish.Cheers, Joe.