While I really like Starscream in the cartoon, it was nice change to see him in the first movie as a force to be reckoned with and not his usual high-pitched chronic backstabber animated self.
Some die-hard fans thought it was heresy/sacrilege/blasphemy, but damn, it was so good to see him strike fear among the Autobot ranks, with Ironhide yelling "It's Starscream!" at the top of his mechanical lungs when he appears in the sky or when he switches between F-22 and Transformer to destroy the squad of jet fighters. It really showed why Starscream is the second-in-command.
Generally, the thing I liked with Decepticons in the cartoon and in the first movie is that they always had more variety in their vehicle forms: aircrafts like Starscream and the Seekers or Blackout, neat ideas like Soundwave, "mean" cars like Barricade's cop car with the "Punish and Enslave" motto or straight up huge motherfuckers like Brawl or Bonecrusher.
Compared to this, the cartoon Autobots seemed "lame", which is why I liked Ironhide as a black SUV with shitloads of guns and quoting Dirty Harry in the movie. I think it'd have been great for the Autobots to have at least one aircaft to "counter" the Decepticon Seekers.
Speaking of Seekers, even though I enjoyed Skywarp and Thundertracker being rebuilt as Cyclonus and Scourge and becoming Galvatron's new close henchmen in the animated movie, I always prefered them as "clones" of Starscream, particularly Skywarp, that black and purple color scheme was great.