These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Also, Misa's appearance as White Rose Mask in episode 29: while it could have led to Misa finally being able to fight alongside the heroes even though she lacks powers, instead she only managed to beat a few Mooks on her own, then get beaten easily by the Monster of the Week requiring the others to save her.
Also also, apparently it was known from the beginning that the original Red's contract wouldn't keep him there the whole season. Therefore, a more meaningful exit for the character than a sudden "oh by the way he's leaving and the guest star of the week is the new Red" in one episode's last fifteen seconds could have been had - especially when you consider how other sentai series handled unexpected departures.