Some say 26" bass drums are slow to respond, etc. I say it depends on the style of music you are playing. Heck, every big band player back in the old days used at least a 26", some bigger.....and then there's the Bonham influence too.....one thing to consider....you may want to go with a longer beater for your pedal so it can hit more dead center for a more true tone.
When you say "bigger shows", what exactly are you saying....bigger venue? Miking up the drums, no matter what size, would accomplish the same thing as going to a bigger bass drum. Is it volume you seek, or a lower fundamental tone?