I would put Clark as NG; he's more an agent of society than most other superheroes, yes, but that's because he perceives his society's current authority strutcture to be a good. He's willing, for example, to unseat a foreign dictator, even though he wouldn't unseat Luthor. He was willing to kill the PZ criminals because, at the time, it seemed to him more just than not killing them. He's had to be talked out of global dictatorship before. There aren't any tools he won't use or must use. He doesn't really have any code or methodology that's more important to him than doing the thing that is most Good. Bruce is the only cape who can compete with Diana in Lawfulness; I'd usually stat him LN, though pre-Crisis he was more LG or NG depending, and of course you get the occasional OMAC-type thing where he's more LE.
You want tricky alignment, what the hell is Tim?
(I think Hestia would be happy with Rama's mighty rod of atonement, provided its use were regular and formalized.
... man, Diana must drive Hestia nuts; her heart stays on Themyscira and she moves her pillow from city to city every two freakin months, regularly cut off from mother, sister and disciple. That is no kind of way to honor the god of home fires and family.)