alrighty, folks, here's some more of that Dark Nova Chubdam, (with legs, this time,) including a couple systems!
First, the front and back views:

As you can see, I've put some of that "chubdam" touch on a pair of superchub legs, with a bit of my own flair thrown in. I did what I could to replicate the "destroy" mode to match the rest of the build. Hope it tickles you guys' fancy as much as it does mine! Don't mind the shield, it's only a temporary stand-in while I try to figure out a more satisfactory unicorn-style transforming one.

Here, on the back, we have a GN drive, reverse-engineered and modified from some of the images in the topmost post. The design was intended to replicate the unit used on the Transient Gundam, from Gundam Build... Fighters? Divers? Eh, you know which one. I'll be modding it again for a later project... Also, don't know how to spec a GN drive for in-game use. Would it
count as a movement system? Either for Trans-Am, or for flying? I mean, most Gundams and other Mobile Suits fly anyways, where Mobile Frames usually don't (like the OG "knightmare" frames of Code Geass,) so... Anywho, to the right, you can also see a couple other GN drives I put together, both of differing design from the one I used on the model, and from each other. One of them's in an "active" state, where it's extended out a bit for use in Trans-Am. They'll definitely be included when I eventually link to the build file (stud.io, btw). Sorry for the other model(s) in the background, they're mostly for scale (and occasionally parts) while I build: I tend to get messy in the process, with spate unused parts scattered around to possibly use later...
Next, here's a pic with a couple systems I've thrown together:

You can see I've come up with two designs for the "Armed Armor BS," as featured in Gundam UC. Good news is, both designs fold back along the arm, like the original! The overall build was based on an old railgun design I found either on here, or in that massive PDF full of community-made frames from a while back. Hard to tell how to spec it for range though, given it was used at an approximation of both Direct and Artillery range in the anime... In addition, there are two Funnel/Fang/Dragoon/whatever pods on the hips (the black masses you see on either side(should I recolor them, perhaps?)), the "lids" of which actually open! Again, not sure what to spec it for with regards to range, because these things are used at all three ranges in various Gundam series. I'm considering putting together a shot to simulate stuff flying out of them at some point, but that's for later. The build of the pods was heavily based on the "Gunpla Builders Partd HD MS Funnel 01" kit, specifically the swoopy-er of the two styles one can build with said kit.
And yes, I will be throwing together some specs for the Dark Nova once I've fully decided what arms and armaments I want it carrying. Might take a while, though, since I'm so easily distracted by building other things...