Thanks for all your replies re:best/famous archaeologists. I chose to use both words, because I'd like my students to be able to do some research on the individuals choosen - that means there needs to be more than a sentence available about them. Unless I actively engage them with the posters, they probably won't even notice....
I haven't decided which to use yet - it's such a long and varied list! But Hawkes, Garrod and Cramp are all on the list, as is Helga Seeden who sounds a force to be reckoned with!
In terms of it seeming unimportant as to whether some was straight or not by the 1980's - none of my students had been born then, and I guess if you're coming out, it's nice to know you're not alone... At the moment, the only person I can think of that remotely fits the bill is Sandi Toksvig, so if anyone can think of somebody who works in archaeology, is fairly well known and openly out, that would be useful!