The Ronan you named had years of appearances and development to become what we was. I doubt he was that in his first appearances. Maybe the problem is that Marvel kills their villains off too much.
No, the problem is that GOTG's Ronan had no personality
at all, even in comparison to other one-shot villains in thousands of previous movies. He was not typical of one-shot movie villains. He was just boring. Even by the standards of Marvel's underdeveloped villains, he was a cipher. And that was a tragic waste of Lee Pace's talents.
They could've given him one speech to establish a motivation, a reason why he hated Xandarians so much. Like, Nero in
Star Trek 2009 believed he was avenging the death of his wife and his civilization. Or they could've made him like the Operative in
Serenity, a character who sincerely believed he was doing the right thing by defending the society he cherished. Heck, they could've even showed that he genuinely loved his daughters and was devastated by their betrayal. Thousands and thousands of one-shot movie villains have been successfully given more personality than Ronan. It's not that hard to do.
They probably just don't want to bother with the one-offs...and they're not wrong for feeling that way.
Hell, yes, they are! They have years of time and huge amounts of talent to put into these movies. They have no business "not wanting to bother" about the quality of any aspect of them. There is never an excuse for
knowingly refusing to do good work. Look at behind-the-scenes videos of just about any feature film. Look at the weeks of design work and meetings and meticulous labor that go into creating props and costumes and signage and set details that will maybe get two seconds of screen time somewhere in the background of a shot, or even get cut out altogether. That's what you can do when you have years and half a billion dollars to devote to making a movie. You have a whole army of talented people that you can devote to making even the tiniest, barely noticeable detail as well-made as it can be. So it is ridiculously wrong to say that filmmakers can't be asked to "bother" to put an equal amount of effort into something as important as the lead villain's characterization just because that villain will be featured for "only" one movie.