Yes, EJO was a good reason to watch Miami Vice. You could probably imagine that version of EJO as a younger version of Adama. He was serious in that roll too.
Fascinating exercise, comparing the roles of William Adama and Martin Castillo. On the surface, both are iron-hard, controlled men who are completely dedicated to their jobs and their code of ethics. Castillo, however, came from a background far more brutal than Adama's (so far as we know at this point), and his self-control was therefore more absolute. He had his vulnerable moments, particularly when an episode focused on him, but most of the time he was as implacable as a force of nature. EJO's genius in that role lay in keeping the man's emotions under 100% control, while simultaneously never letting us forget they were there.
He does the same with Adama, of course, but as a character I think William Adama has more balance and nuance. He can be ambushed by circumstances more easily, has had the occasional endearingly awkward moment, and is more willing to relax his guard every so often. Could you ever see Castillo using Adama's "and I can dance" line on a lady? Not a picture that comes easily.
The most telling moment of comparison for me so far came in "Tigh Me Up, Tigh Me Down". The scene in Baltar's lab was priceless, with Adama simultaneously confronted by Ellen Tigh's baseless accusations, the Colonel's hurt, angry frustration and the President's suspicions, while Baltar is desperately trying to pretend he's not involved. If Castillo ever wound up in similar circumstances (not too likely to begin with), he would simply cut everyone to silence with a scathing, laser-eyed stare and begin restoring order. Adama is certainly trying to restore order, but in his eyes we can see the faintly desperate look of a man wondering when he lost control of the situation.
So, while I love both characters equally, I must say that, for me, William Adama is the finer, more human creation. Edward James Olmos is another actor who only gets better with age.