From a storytelling point of view, what was interesting about the original Transformers and G.I. Joe series from the 80's was that they broke one rule of storytelling: when making a team, make every character count.
Obviously, both shows existed to further the massive toy line they were based on. And what was interesting was that they managed to sneak all of the characters and vehicles into the cartoons. In fact, there were too many characters to keep track of, and some characters appeared in an episode without a prior explanation. (Of course of the two shows, I found Transformers to be more stable. Subsequent additions to their cast such as the Dinobots were given ample introduction.) Yet despite that "flaw", we as viewers loved it.
I think future storytellers realized that flaw. That's why in the subsequent American sequels of Transformers and G.I. Joe, their respective casts were trimmed down. The Transformers CGI even cut it down to five characters on each side and moved on from there.
Another comparable show was Justice League Unlimited but the franchise started small (the first few seasons of Justice League) before moving on to this massive ensemble cast. Of course at the end of the day, you can't tell a story by focusing on a hundred characters and Justice League Unlimited pretty much tackles it the same way Transformers and G.I. Joe managed to be a viable series during its time: with each episode, the story focused on a few central characters and the rest were "extras".
Despite knowing that, it still makes me wish that the Transformers franchise would return to the days of hundreds of robots on each side, duking it out.