Is there any chance you might do a version without the extra pair of nacelles? I have always hated the basic Mars concept because of the extra nacelles.
Wouldn't be a Mars then if it didn't have 4 engines. But I suppose I could take the second set of warp engines off, and if GAFY's willing to make some modifications to window sizes, I could then resize the resulting kitbash to be between the Mars and the Connie. But that means I'm gonna have to separate the torpedo launchers to maintain their size to help further balance the size of the ship.
But that would ruin the whole point. I would like a big dreadnought, but with a single pair of nacelles. It's just a matter of personal taste. I would do it myself, but it crashes Milkshape. I suppose I could use M6, though it would be a lot more work. All you'd have to do is open the model in whatever expensive program you use, select the nacelles, and delete. Surely it wouldn't take more than a couple of minutes. Even if you are not fond of the result, couldn't you do it just once for this long-time player and wanna-be kitbasher, please?
If you just insist that it has to have four sets of warp coils, maybe you could make double nacelles as on WZ's Carolina and Midway, by giving each nacelle two plasma things on the sides instead of one.
Although if you must significantly alter it, I would suggest you remove the botanical garden. I somehow doubt that dedicated war ships would waste so much space on non-military facilities with big windows on the side making such appealing targets.
The Mars was an early TMP Battleship, eventually replaced by newer, more efficient battleship designs, which didn't necessarily use 4 warp engines. At least that's how it goes in Trek fanlore.
Would a Connie still be a Connie if she had a Sovereign-like saucer and integrated secondary hull? Not really. Would a Miranda be a Miranda if it had a secondary hull? She'd be more of a Connie if that were the case. That's why I said if the Mars had only 2 warp engines, she wouldn't be the Mars.
However, if such a request was a personal one, and only meant for personal use, I don't see much of a reason not to do it, so long as the model itself wasn't released or shared with anyone. I'd have to rearrange the damage points on the ship, but that's easy enough to do.
Oh, and FYI, who says I paid a dime for 3DS Max?