Taldren made the original model, well actually it comes from Klingon Academy, so whoever made KA made the original model, their version has 'Excelsior style' secondary hulls, though they're not really limited to the Excelsior. When StressPuppy altered the design to make a TOS version there is no TOS equivalent of the flat-topped hulls the original (TMP) Yamato used, so he just made some oversized Connie versions by the looks of it.
Look on modelviewer at the fbb.mod file, the original Taldren BB, or hell look at the pics from KA that Chris Johnson posted in this very thread, that is the original design of the ship.
The new one looks good so far, though it shouldn't have those neck parts at the front of the sec hulls, dunno what they're doing there as they wont connect to anything, the hull tops should be inline with the top of the saucer.