I'm fine with the current format. But Four companions have entered the "God Mode" cheat, and I call hax on several others. That's not really necessary. Donna had a real character arc with growth and such (despite then hitting the God Mode cheat), and so did Mahhhhhtha, though I had problems with her run as well. Mostly that it was 45% about Rose. Also, that she gives the Doctor God Mode. Amy and Rory had a complete arc in the first series of Smith's run, and then they...they had the same arc meandering through the rest of the time on the show.
Rose is some selfish brat who starts off fixated on the Doctor and ends up fixated on the Doctor. At best, you could argue series four led to some small level of change, but it ends pretty much back where it started. Except she's hot for 10.5 because...human?
Clara strikes me as very similar, in that she's manipulative and self-centered. She's more smug, but she's doing much of the same. Her crisis when 11 regenerates into 12 is that he's not young and hot anymore and she can't use her boobs to get her way or something. Christ, Moffat even described it roughly that way.
I think this is more down to writing than format. I was fine watching Donna grow over series four. I was sad when she left. But Rose and Clara...ugh.
Yeah now that you mention it, he kinda did.
Maybe Davros was really angry about the Star Wars prequels.