Gundam Battle Operation 2: Guy Helmuth's Rick Dom II Proves That Anime Swords Defy Gravity 

Space units already tend to have lower HP, and often lower melee resistance, since they're designed to be used in an environment where you can just get out of the way much more easily. The Pale Rider Space only has 13k HP+ a shield at 400, and it doesn't scale higher than normal at other levels. And space doesn't care about part HP nearly as much since legs aren't breakable, and your backpack is very easily breakable in the relatively rare circumstancen that someone can actually hit it enough. But it can also fix them up with HADES, and you're likely at the point of wanting to activate that if your legs were hit enough to be broken or nearly so. Besides just adding more units to ground, I think they also just want data to buff them (they only use A+ rated data to try and make sure that all the data is from people who should be good enough to bring suits to average performance on a balanced suit), and they just didn't have that kind of data with just space maps. Also likely that they're seeing if any other features like the sword acting as a shield, the giant blast radius on the GM Cannon, or overboost+dodge are things they could safely add into various new units or buffs.

You fire the MG when there's no other weapon to realistically use, or its dangerous to get teammates caught by a stun, for passive damage. Though I agree that you otherwise should try to set it up for the most numbers of quick staggers closing in, hopefully using the beam last to safely land the big melee damage. Though I personally hate using the downswing on something like this where it hits twice in slightly different spots while you drift. At least in space the weapons size could make up for inertia or hit enemies above, below, or way off to the side. My first 7-step was Zaku IV IP, and I never could make it work without luck , even when it was in a really good spot at 700. And there were a lot more small units being used at 700 then, making for smaller hitboxes and downed suits that were often impossible to hit with the knuckle dusters.

It's been out for a good long time, so check the DP store. If not there, hopefully it'll turn up in Recycle Tickets from time to time.

Yup! GM Cannon Space Type, Zaku Minelayer, Pale Rider Space, and GP01Fb can all sortie to ground maps now too!