Well designed is well designed.
If a feature has reason behind it it will eventually look OK. The P90 looks ugly until you realise what it is designed for (capacity and compactness - at the expense of ergonomics and barrel length).
Oddities that look a bit odd to me, and may indicate what the weapon is optimised for.
The stock
Collapsing/folding stocks make a lot of sense for storage. Solid stocks make sense from a ruggedness point of view. This stock appears to be slightly collapsible and probably removeable (the wheel lock mechanism just behind and above the trigger I assume it to detach the grip and/or stock). There is a button on the stock which I assume is to allow the stock to be recalibrated by sliding up to rest on the back of the weapon, or out to accomodate those of larger stature. Depending on the kick of the weapon this could be a problem, as a 5.56 I wouldn't worry, this type of stock on a .50 or shotgun I wouldn't implicitly trust depending on the lock mechanism.
Another possibility is putting a spring mechanism into the stock. This would be an intriguing option of questionable worth, more appropriate for an enormous kick weapon (PGMP's for example).
Sights
Enormous iron sights looking vaguely like the dorsal fin on a shark seem a little over the top. Like a return to a 1950's car fins. I can see why (to lift the sights over the mounting rail) but something more subtle should have been acheivable. The sight mounting rail looks fairly standard, though it looks like a low height scope might be partially occluded by the rear iron sight. That might be just my perception though.
The bolt.
Something looks wrong there. I can't quite put my finger on it though. Lots of open grooves that I am unsure of why they are there.
Foregrip.
Chunky enough to mount a small grenade launcher in. Also chunky enough to keep the barrel down as well potentially. The attachment points for a bipod are also a nice touch (I assume that is what the open grooves at the very front are for, they might just be venting).
To me it looks like an attempt to muscle in to the military carbine market, an area already overly full.
Just my 0.02 creds