Cool, is that the lastest
IG flyer kit?
I think it would make a great basis for an Imperial shuttle or dropship, or a large bomber for the Orks.
For the Imperials, I would remove whatever that is sticking out of the nose (is it supposed to be a gun?) and round the nose out or leave it blunt and add some sensors or smaller guns. You could add Valkyrie or
SM flyer turbine intakes to the front of the engine nacels, then extend them back across the wing and have the exhaust nozel at the rear. Or remove the wings entirely and add a large engine cluster at each wing root if you want more of a dropship look to it. For scale reasons I think you should close up the lower half of the "window" space at the front and have smaller windows along the upper half of the space.
If you want to make it an Ork machine, then just do all of that, but with less finesse, and liberally garnish it with guns. Also, if it has a rear ramp you could have a large bomb dropping from it like a MOAB.