I think it was Spielberg who pushed for the "humor" in TF.
I didn't mind the humor; I didn't like the limited character interaction with the decepticons, I didn't like the off screen fight between Prime and Megatron, and I didn't like how the cube turned everything evil (including a car, xbox, and mountain dew machine).
Here's a plot idea for TF2:
A Decepticon sabatoges the Autobots goodwill on Earth by posing as an Autobot and destroying an international monument, causing various Governments to label any Transformer as an enemy of the state. Starscream assumes command and returns to Earth with reinforcements, intent on taking over the planet for it's resources, but Soundwave and Barricade secretly find Megatron and revive him. A few more autobots arrive, but Bumblebee is ambushed by Decepticons and Sam & Mikaela are captured, luring the Autobots into a battle that, ultimately, is a trap since they'll be heavily outnumbered.
That's all I've got and it's just an idea anyway.
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