I've modelled some non-canon Stargate ships that came out pretty good. I call them the X-305 and the X-306 respectively. The X-305 is a follow-up design to the Promethues (X-303), and the X-306 is a new form of Super-Carrier, capable of carrying 1 X-305 in each of it's hangar bays, or a full squadron of 302s, depending on what the mission requires. The 305 itself, is capable of holding a smaller contingent of 302s in each of it's hangar bays. Needless to say, these bad boys come well equipped
Size I have not determined, however, the X-305 should be slightly larger then the Prometheus, and the X-306 would be somewhat larger then the Daedalus. It would have to large enough to fit 2 305s into it's hangar bays at least. I see both these meshes as completed, and they are standing by in 3d Studio Max 6 format.