When you say great, do you mean in terms of acting or in getting the character right?
Because characterwise, they totally botched his character. Telling Clark to let children drown, never being able to make up his damn mind (did he want Clark to use his powers for good or keep a low profile, he constantly kept flipping his positions) and that stupid, contrived "noble" choice that made absolutely no sense (Nolan likes to do those a lot, see DK, DKR).
"It's okay Clarke, just let me go. I'm happy to let myself die for my dog even though I'd be leaving behind a wife and son and yeah, you could save me with your super speed and probably no one would notice because of all the chaos but better not take the chance because I'd rather die than get over my weird hang-up of you using your powers for good. I'll just let the tornado whisk me away even though that's not really how tornadoes work. Also you should probably all get out of that underpass, it's like trying to avoid lightning by hiding under a tree."
Acting-wise, he was Kevin Costner. But that's my humble opinion.
On Lois, I was amazed at how incompetently the writing for her character was. Trying to sell her as some tough journalistic reporter by making her first line a dick joke and saying she won a Pulitzer prize? It came off so forced and disingenuous. Like they were fulfilling some sort of quota for trying to pass off a woman as a strong character instead of actually writing a strong female character.