Probably a more interesting question is design purpose. Why was the Odyssey-class so large compared to the already large Galaxy and Sovereign-class starships? It is like trying to cram the firepower of the Sovereign in with the capacity of the Galaxy. Was the Odyssey suppose to carry families on decades long voyages outside of Federation space? Because that was the Galaxy was designed to do (though never did).
The Constitution III-class starship, appears to be designed for regular exploration duties like her 23rd century counterparts. Long missions perhaps, but no more extravagant than those of Pike's and Kirkj's time. Seems like a nice point between the Excelsior and the Ambassador in terms of size, and with much better technology. Which seems like a good spot for an explorer. Large enough to do the task without being large for larges sake (like the Ambassador and Galaxy-class may have been)
The Constitution III-class starship, appears to be designed for regular exploration duties like her 23rd century counterparts. Long missions perhaps, but no more extravagant than those of Pike's and Kirkj's time. Seems like a nice point between the Excelsior and the Ambassador in terms of size, and with much better technology. Which seems like a good spot for an explorer. Large enough to do the task without being large for larges sake (like the Ambassador and Galaxy-class may have been)