I think they look fine, and they look like they would be broadly useful for a variety of sci-fi purposes other than Death Fields Raumjager, such as Eisenker, as mentioned by John WIlson.
They don't look as heavy as the Grognard heavy weapons did, but then that seems appropriate for what would presumably be a more mobile, portable force equivalent to paratroopers, which seems fair to me.
I like the heavy machinegun the best.
Not sure I'm entirely convinced yet by the flamethrower or that shoulder-fired weapon the guy on the far left of the group render shot is using, but that could easily change with a different perspective view.
The tablet computer the mortar crewman is holding is great - that sort of thing would be exactly the sort of thing I keep hoping to see more of, and would be great for a variety of other purposes - programming and operating drones, administrative tasks for guards and officers for raid or sneak-by-the-guards scenarios, a device for hacking into and looting secure bases or storage lockers, a scanner for medics/corpsmen administering first-aid to casualties.... naturally it's not going to be for everyone, but I like this sort of non-combat bit, especially for use in role-playing games and so on. Radios, cell phones, demolitions charges, mine detectors, hand tools, and that sort of thing would be great, as long as there's room.
EDIT: I should add that I'm not likely to be a big customer for Raumjager sets - I might pick up one of each of them eventually for the bitz and for general-purpose sci-fi gaming use. For that purpose, these ought to be great, but customers buying and building Raumjager wargaming armies might see things very differently!