Golden Age: You’ll see a remarkably progressive relationship considering the era. And could still be counted as remarkably progressive today! Steve never really looked threatened by Diana’s superior powers and being a smart boy, was happy to see her when he needed saving! :)
Silver Age: Due to many cultural and social reasons, Diana’s feminism was de-emphasized and her relationship with Steve was made more conventional (I’ll be delving into these reasons in the essay I’m writing for superhero_muses). Suffice to say that both could be written badly here, so if you come across Diana as incredibly wimpy and Steve practicing Trevordickery, consider the times! ;) Remember, this is the era of Superdickery and Lois trying to trap Superman into marrying her. Steve gets to constantly ask Diana to marry him. Luckily I got to read some of the better stories and there are gems amongst the dross. The core of the characters manages to shine through DC’s often chauvinistic/misogynist treatment of this couple in these years.
Bronze Age: They killed Steve off in 1968, brought him back in the ‘70s, and he was Steve Howard with dark hair (Steve Trevor was supposed to be dead, after all) and knew Diana’s secret identity and everything about her. Some interesting stories with the two of them, but then they killed him off again! Sheesh!
Diana’s memory of Steve was erased (insulting to the dead person, IMO) and then in 1980 a Steve Trevor from another dimension crash-landed outside of Paradise Island (See! It’s Destiny! ;) ). Eventually her memory of the original would be restored but during the ‘80s up until COIE, you get some of the best of the relationship (especially Golden Age) updated to a contemporary setting with the Women’s Liberation movement as a background. It was 'classic' Diana/Steve during these years and satisfying to me as a reader.
So, if you pick up any old issues, CAVEAT EMPTOR with the Silver Age, and smile at the rest! ;)
The essay I’m writing will give you a lot more details and my take on them. I like to take the best of the relationship in my current fiction and showcase the partnership, loyalty, and love. :)
Also, we may (or may not) get a positive, modernized version of the relationship in All-Star Wonder Woman, which apparently is still a ‘Go’ as a project: Interview with Adam Hughes. I will probably plunk down a few shekels for at least the first issue 'til I see what's what. ;)