Superhero Sandbox has some pretty cool plot names - since each event is a whole thread down there, we tend to go through a lot of titles. Some of them are really interesting or creative. You could go scan through the ones in there and see what you like or don't like or what's interesting that you hadn't thought of before.
I know I kinda tend to go thematic when I'm titling things. One of my characters (mostly on old RPF) had electric-based abilities, so a lot of her thread titles ended in -ion. So, things like "Communication" or "Resolution" or "Aspiration." Often a lot of my titles have double meanings - like "Aspiration" was largely about learning to function with an artificial lung after a bad injury in another thread. Another character I'm currently running in Sandbox has an energy/matter absorption ability, so a lot of his thread titles will have the word "Matter" or "Matters" in the title. My idiot magic child I had all thread titles be two words starting with the same initial sound that formed an easily referential phrase but also had at least one magical meaning in there - so "Standardized Spelling" was about learning basic magic spells, "Diabolic Details" had devils in it, and so on. For the record, that is way too complicated.
I try to think about what sort of character(s) is(are) likely to be involved, what the plot line is going to be like, what the location is going to be - all those can be good things that you might want to reference in a title. Sometimes short snappy titles can be good for grabbing attention, so can alliteration or assonance. Puns can be good too, if you want to go that route, especially if it's not all that serious.
A lot of it is also just a matter of personal taste or style. What I like might not be what someone else likes, so it's good to look around and see what a lot of options are. Sometimes you just find that something "feels" right, and you don't really know how to describe it other than it seems to fit.