This looks like a pretty good model. I've wanted to build a few of UHU's models in the past but never seem to get there in time. A pity, really. At least I have the option to build this one.*
Let's do some math. According to Starship Modeler a 1/144 Ares measures 83mm in diameter. A 1/80 Ares measures 6 inches in diameter.
83mm x 144 = 11,942mm = 470.5" = 39.21'
6" x 80 = 12,192mm = 480" = 40'
The biggest diameter former in UHU's Ares measures 119mm across. This sits a little above the fattest diameter of the ship so I will fudge and call it 122mm in diameter.
12,192mm/122mm = 1/99.9 scale
Just to double check let's look as some other features. The internal doorways measure 22mm in scale height or 7.2' in real height. That's acceptable for a spacious luxury space ferry.
The external doorway measures 20mm in height or 6.6', again acceptable.
The passenger cabin seats measure 5.5mm in depth (21.65"), 8mm in width (31.5"), and 11.5mm on the back (45.3"). Those are some spacious seats! The flight cabin seats are a bit smaller, almost exactly scaling out to the large chair in my own office.
In Sci-Fi spaceship land there are no absolutes, but I think it's pretty safe to call this one 1/100 scale or close to it. Please feel free to double check my measurements.
I'd need to blow this up 286% to build it at 1/35 scale. Could happen.
-Doug
* Yes, I know you can play Where's Waldo and maybe find all the files. I hate that game.