Lack of imagination. No one thinks to try snake-charming the cobra.
No explanation for Tayla staying away from helping her friends.
With elf and fairy magic in decline, it is not shown how Peter gets out of the unremovable tuxedo of Agent Swift. (It could be explained that the suit is affected by the magical drain as well, but if so, how can one account for it never losing its power of super-speed, nor why Peter would take it off before their perils were over.)