Thanks, Albertese and Mytran!
This is exactly what I hoped for. After Praetor said in an earlier post that the 305m of the Refit are pinned down so well, I hoped for a way to have this and the upscaled TOS ship (around 1067') too.
Also, the 1164' and 1235' versions are an interesting alternative. Aside from solving the cargo bay issue on the Refit, we could also have a bigger TOS ship to increase the size difference between her and the NX class. Also she is not so big that the windows look too oversized (maybe a bit, but still I think acceptable). And last but not least, the two Constitution classes don't look too small compared to an Excelsior class of around 600m.
Regarding the deck heights of the Constitutions, if the ship has a heavy and sturdy skeleton to which the pressure compartments are fitted, maybe that also justifies higher decks. The Excelsior with her new SIF enhanced truss and beam design could then have lower decks, because much of the structure between decks wouldn't be needed anymore.