I am very excited about this race and I like the way their armors look but I also I'm not digging the big beige paddle look of the weapons.I prefer the factions that are more "good in their own interest", selfishly good, and can be seen as a villain to someone with equal intentions but clashes with theirs, which I'd say most factions are but are also open for different sides. That said it's hard to really say whether Oathbound are meant to be inherently good or blinded and ignorant in their vision, seeing as recreating the Star Union maaaay not be the most noblest of pursuits nor forcing everyone under a single banner again when coexistence may be the better option.
But that's entirely up to your own interpretation and how you did the campaign, as there's little context to what's actually the right path to take. I do get a feeling though that Oathbound are meant to have good intentions but that those intentions could be viewed as authoritarian dictatorial rule and that they may not accept anyone wishing to remain independent, branding those factions as renegades and rebels of the Star Union. Not all Oathbound probably, but some in power. It'd atleast open up more sides to it if their noble-bright exterior hides something potentially darker or less black and white, such as their view of their cause being noble and good may actually be more villainous for others.
As for Oathbound's aesthetics, so far I got mixed feelings and it's not that they're humans. There's shots of what your commander can look like and their customization is interesting. There's also the big mech unit that looks badass and the paladin champion as well as seer looks quite good. But then there's shots of what I'd assume is the core unit with the big axe-polearm which their suit looks very... eggishly bland and their weapon simply resemble a big paddle. There's also another mech (tier 2?) in some shots that's smaller with shield and sword, with the shield and sword having rather... odd shapes to them, don't know what to feel about it.
It's like they're meant to look very stylishly futuristic and different from the other human factions but kinda ends up looking all over the place. Amazons looks fairly futuristic and stylish, but there's still a feeling of functionality, a continuous theme. Oathbound look all stylish but no functionality, the theme being to kinda not look that way to convey they are "beyond it", but to me their armor and weapons sorta look more fake and plastic. I hope my initial feel for the little we can see of them so far is wrong and I warm up to them, as I am very, very interested in their playstyle.