I am surprised that I am only the second person to write a review for this series, (which may simply be a testament to the fact that it is indeed an obscure one).
I love the Swamp Thing. Both Len Wein's and Alan Morre's manifestations of him... and I find that this series approaches the character with great affection, and attention to his most important traits of compassion and wisdom. His moral code is complex, and his diplomacy restrained. He does not intervene in forceful and demanding ways, (as many super heros do), but rather works his miracles from the background, all but anonymously.
Now, it is possible this series was a victim of viewers' unfulfilled expectations of watching an entity of fury and unstoppable, unrelenting force demolish evil in every episode. It is true that he has such power, and he does indeed flex it when necessary... but what is most essential to his character is his remarkable ability to heal, care for, support, protect, console, and love all things alive. In this respect this series is a complete success.
Beyond the refinement of character, the series is also endlessly imaginative, and profoundly moral. The plots are original, and the script couldn't be any other way. Sometimes The Swamp Thing will say something, a bit of advice or an observational musing maybe, and it will just hit you hard for some reason, deep within.
I give this series 10 stars for it's painstaking attention to the things that make Swamp Thing so endearing and fascinating. I strongly recommend it, and this is coming from an avid fan of the graphic novels.