All right, since all the cool kids are posting about Chuck Jones, I'm feeling left out. So here's my take on Chuck's artistic ability and whether or not it waned in his later years. Cut to the chase - NO, of course he was not drawing at his best in his old age, but even his drawings for the limited-edition sericels that he was mass producing to satisfy the animation collectibles market that was springing up, were pretty damn good when taken on their own terms. I think ol' Chuck was no more guilty than other "Animation Legends" that were out making some easy dough in their golden years by exploiting their illustrious filmic past. Friz Freleng was doing it too, but if you take a look at the sericel images in these two runs, I think Chuck's drawings were far better than those of Friz. However, I don't believe that Friz in his prime was ever as notable for his draughtsmanship as he was for his directing skills, so I don't hold it against him.
To be sure, Chuck's drawings on the sericels and also the illustrations he did for his two memoirs, "Chuck Amuck" and "Chuck Reducks" were pretty off-model, as they say, when compared to any of the cartoons he directed back in his heyday at Warner Brothers. But when taken out of context, his drawings are still examples of damn fine cartooning nonetheless! I always suspected that when any of the oldtimers, once having long retired from their respective studios, were basking in the glow of the recognition and popularity that came their way later on, they basically didn't care how accurate their sketches were to the original character models. They were a bunch of old farts just enjoying all of the overdue attention they were now getting from their legions of fans and, free from the constraints of actual cartoon production, were allowing their own personal artistic styles to take over in the same manner as their handwritten signatures. If the characters weren't exactly on-model, so what? Being a beloved oldtimer in this industry buys you a lot of slack, in that, who is going to tell you that you no longer know how to draw the characters that you had a hand in originating? Guys like Ward Kimball and Bill Justice from Disney were taking the same liberties with their characters that Chuck took with Bugs and the gang, but any fan lucky enough to get a quick sketch from these delightful old codgers treated it like gold (as well they should), despite whatever inaccuracies to the design had taken hold with the passage of several decades of their being away from the animation desk.
For the record, by the way, Chuck Jones was also my favourite of the Warners cartoon makers. Even back when I was a young kid catching them on the old "Bugs Bunny / Roadrunner Hour" for the first time, I noted that the cartoons I liked best mostly seemed to be directed by some cat named "Charles M. Jones". They always seemed very sophisticated, though sometimes given to self-indulgence, in retrospect I suppose. It was years later before I delved into the history a bit and learned something about the various animation greats at both Warners and Disney. If memory serves me, I think one of the first times I actually saw Chuck Jones at length on TV was in an interview he gave on "The Dick Cavett Show" sometime back in the 1970's on PBS. I vividly recall what a fun interview it was and that Chuck did seem to come across as a guy who loved to hear himself speak. In fact, it seemed to me at the time that both he and Cavett were two of a kind, engaging in their know-it-all banter, with Chuck likely quoting Mark Twain and Cavett quoting back with Groucho Marx. But, as I am also often guilty of being a bit of an elitist blowhard, I felt a certain kinship with these guys!
In his post Warners animation career, Chuck was pretty hit and miss. I still consider his "How the Grinch Stole Christmas" to be the gold standard in animated TV specials, but his three adaptations of Kipling's stories from "the Jungle Book" later on were good, but not great. Sadly, his very odd version of "Carnival of the Animals" with Bugs and Daffy I consider to be pretty abysmal, which proves that even a once great director like Chuck was not infallible. And I don't think any of us are being disrespectful for pointing out such shortcomings either. Chuck Jones was only human, after all.
To see a retrospective of Chuck Jones art, running the gamut from "Classic Chuck" to "Make a Quick Buck Chuck", please take a look here on John K's site.