Mockery is a good word and your examples are right on and those episodes including the one where De Lancie's son made an appearance flatly destroyed Q. Even on TNG I thought the writers were running out of ideas for Q and returned to form in "Tapestry" where Q was the observer and a teacher for humanity; guiding us to understand the stages of our lives creates our own unique story. Then after "All Good Things..." for me a wonderful conclusion to what Q is about and was preparing us for mysteries to come... like a new job, a new objective for all of us we will have to face. The challenges of the Q is not what they face but what we will eventually have to and what will become of us.Comedic or mockery?
By VOY, there wasn't much left they could do. The three VOY episodes were mixed bags but once they took this big mysterious place into the old west in a desert so we the audience could "understand it", the Q were demystified completely. Oh look, it's a supernatural by supernatural fritters and we're given low budget rusty 1940 gas station to relate to.
It didn't help that the Q of all beings would be so splintered by a huge contrivance of forbidding suicide. That started the ball rolling.
Still, the Q and Gray episode, before going into 1950s desert land, had a few humorous quips. They just can't compensate for the rest of it.Q easily could have remained without the need to visit his plane of existence... Unlike with Sisko, he feels as much at home with Janeway as he does with Picard.
After "The Q the Grey" I'm still pissed off Janeway did not accept having sex with Q to get her crew back home in "Death Wish" after learning their interpretation of fornication was the touch of a finger??? Wow. Not her best moment to think about herself than looking in the best interests of her crew.
Could there been episodes which could fit the Q on Voyager? No.
Reason being was Voyager was going backwards than moving forward for the Q to have a purpose; this being knows what's out there and explorers who are going to the farthest reaches of the universe need a practice test before actually encountering the universes full forces. So when Voyager delivered "Death Wish" I knew the idea of Q was done, stripping layers upon layers of interest in the character into something less threatening and less dynamic.