I think a 16 team playoff would be better for the team I root for (and the team you root for) but in the grand scheme of things whether it's at 12 or 16 won't change who the champion will be.
I agree, in principle, the larger the field, the better % of ISU having entry point.
My tendency is to consider "what's best for us" separately from what makes most sense for CFP & CFB more generally. I suppose the latter matters less and less and time continues, but ... well.