The three "Coneheads" (Ramjet, Thrust, and Dirge) are drawn way out of scale compared to each other when one of them transforms. The others look like they would fit inside their comrade, even though as robots, they are equally big.
When Powerglide is riding the carousel with Astoria, he is drawn horribly small, when in fact he is a giant robot.
There is no way a frail female human like Astoria would survive the abuse she gets from Powerglide without any injuries. She literally gets smacked around by her robot love.
When Powerglide offers Astoria a parachute, she completely disappears, save for her skirt, which continues to magically float in the air.
When the Decepticons are trying to get information out of Astoria Soundwave's heads is incorrectly all colored dark in one scene.