The look of them is very utilitarian and even dieselpunk-esque. The pockets could be used for everything from technician's tools to spare magazines for a pistoleers firearm.Giraud, that's the guy!
There's a lot of interesting fashion that you might want to look at, seeing as how those pants are central. Are you into weird designers & stuff at all? I'm a techwear/weird clothing nut and there are some real world pieces out there that remind me of things that could exist in the same universe as the awesome set of pants you drew.
I know it's not the exact same thing but there's inspo to be had in the logic of the pocket layouts and in concepts like curved-leg pants that simply hang differently on the body. A lot of the astronaut/alien style you've got going there has already been made into stuff one can mine for details.
If you ever want to sperg about this stuff or run something by me, shoot me a message, I think you can see I love picking this stuff apart.
EDIT - are you still gonna add to that drawing?