Agreed. There should have always been a steady progression regarding the amount of time and influence the TFs had in the story. Their exposure in TF1 was perfect. TF2 went the more robots route instead of allowing the audience more time with the robots introduced in the first film, and thereby derailed the series in ways from which it has yet to fully recover. TF3 was primarily tasked with damage control, but did manage to depict the TFs in a manner that attempted to re-engage the audience; however, in some ways, it was too little too late.
I understand that TF4 has better characterization of the robots and more scenes containing them, but since most of the characters are new, its asking a bit much for the GA to care at any depth. If I had my druthers, I'd bring back Lennox, Epps and Ratchet in a story that focuses primarily on the TFs dealing with the after effects of the events and points dropped in TF4.