Here are some more weapons I believe are being used by Sentai fans to attack Power Rangers and flame it on:
I've read in Youtube of fans berating Power Rangers SPD saying it's not as great as Dekaranger. I think it has to do with some overacting cast members (it's always better to underact than to overact) and that the Omega Ranger was just a ball of light.
Magiranger seems to be in the list too. I guess it has to do with Mystic Force's lack of episodes plus the poor writing of Bruce Kalish.
Boukenger's an obvious one. The fact is Operation Overdrive was so berated that some PR fans liked Boukenger better IMO as if it were a Saban season never mind the differences. I have to admit that even some people who are PR>Sentai type of fans liked Boukenger better and it had to do with likable characters, more developed plots and better humor which I agree.
Gekiranger has also been used to berate Jungle Fury which was too short for them.