9. Malekith
Malekith is one of the latest in a long line of Marvel Studios supervillains who fans and critics alike have taken shots at for not being well developed enough. A big part of that is a result of bad guys like this being killed off after just a single appearance rather than fleshed out over time (something which Marvel must realise has worked brilliantly for Loki). Seemingly crushed and killed by his own Dark Elf Flagship, there's surely a way Marvel could bring back this longtime Thor villain for another round with the God of Thunder. Loki has faked his death in twice, so it's definitely not outside the realm of possibility. In fact, Malekith seems perfectly suited for a role in Thor: Ragnarok. The villain actually returned to life in the comic books not too long ago, and has since been responsible for cutting off Thor's arm. Christopher Eccleston was also great in this role, so whether it's that, another story from the comics, or something totally original, seeing Malekith the Accursed make some sort of return in the near future is undoubtedly a must.