Marvel is a big enough fandom to support an entire topic, @Spector_Otterquill.
Hm... you might have a point here, and I'm clearly biased, so I'll let @Hanna_brassheart decide on this one. But personally, I believe that it might be big enough (or actively used) to stay as a topic.
This is a big subject, @Spector_Otterquill.
I don't know about you, @Spector_Otterquill, but this topic could easily fit into it. O_O
I forgot this existed to be honest...
Alright, the problem here, @Spector_Otterquill, is that your argument is that because that there are smaller branching topics stemming from those topics, it makes this topic perfectly fine. But if you want to take a look, you won't find any smaller topics concerning specific bands or artists. At least, you didn't list any.
Marvel can stand by itself because it is not solely about movies, Marvel is a comic-producing company. The entire Marvel universe and things about it can be discussed in its own topic because it's not ALL about movies. Get what I'm saying?
Same thing with Tron, but on a smaller scale.