I no longer argue the authenticity with @unifin, because the way I understand it, he isn't going for the proper Hiigarans in the first place and their established design rules. Since this mod is set in the future, all my arguments are irrelevant.
So is this authentic Hiigaran? No. It has about 200% amount of guns and 150% geometry complexity. Actual HW2 Hiigarans in comparison are smooth and rather gunless.
But is it a cool ship? Yeah, most definitely. If I saw it out of context, Homeworld wouldn't be my first guess, but the ship is bloody impressive and this isn't the HW2 era. The more subtle Homeworld stuff just isn't Unifin's thing and pretty much all of us are guilty of making things that are way more exciting than they are authentic (like me a bit literally now). And this is a mod, so let's play and unleash our imaginations. This is what it's generally for.
I should mention that I like this take on the Destroyer / Battlecruiser in-between ship when it comes to its overall shape. Flat rear end, thinner front end and seeing both Destroyer and Battlecruiser in the profile, that is done really nicely. It does indeed look way too massive for the ship of its class, but the transition is done very well.