These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Moral Event Horizon: The Mad Viking killing his own granddaughter because she disagrees with his beliefs.
My Real Daddy: Len Wein had a hand in both Swamp Thing and Man-Thing, but the former is best remembered for Moore's run, and the latter for Gerber's.
Ugly Cute: Especially in Thunderbolts, Man-Thing has very expressive eyes which, combined with the tendrils of his face, just sort of make him look adorable.
The Woobie: To put it simply, Man-Thing's life sucks. He was turned into a terrifying monster, can rarely (if ever) socialize with others because if they get scared by anything he'll burn them, he constantly gets dragged into bizarre adventures when he just wants to walk around his swamp, and most of the people he's ever been close to are dead by now.
Also getting his mind and memories back always makes things even worse for him. He either feels fear and gets incinerated by his own powers or loses his ability to properly control his teleportation powers.
The CG on Man-Thing itself is mostly good, except for the red firefly-things in its eyes.
They Just Didn't Care: Other than the title, it's just an typical monster movie; almost none of the characters or ideas of the comics made it into the film. In particular, they replaced Man-Thing's "touch that burns whatever feels fear" power with... tentacles.