That could work nicely for continuity purposes, barring the Farragut's actual appearance on-screen as Constitution-class.
Well, there's nothing to infer that the Farragut that's flying around during TOS is the same Farragut which Kirk served on, though it's commonly assumed to be the case.
In my mind, the Farragut is the ship I saw in a classic Trek graphic novel, which was a Constitution-class ship. But that's a matter of personal taste... we've never been told anything either way.
I actually really like what Warped9 has done here. I'm pretty impressed that this was done in Photoshop. Ray, is this using the recently added (if I've read my magazine articles properly) 3D capability in Photoshop, or is this all literally 2D?
Either way... beautiful work, and yes, very much "of a piece" with the Star Trek I've known my entire life.