sentai fans, which series should I watch?

just whichever you think is good, better if it's more modern but not necessary if you think one of the older ones show the better side of the franchise/genre

Oh, gosh, that's a difficult one in my opinion.

Like one of the more popular recent ones was Kingohger and it was because it was one of the few series that didn't lean back into the standard Sentai formula

Well, that and the non-binary rep

Back on Gunpla : nb rep? Kingohger it is then

XD yes!

Rita Kaniska/Papillion Ohger.

(They're also complete goofballs who, when not overworking themselves, will hide in their room and pretend their collection of plushies talk to them)

Gokaiger was the 35th anniversary series and has a bunch of explained throwbacks and cameos. The team is a crew of space pirates who can turn into any previous sentai.

I can hook you up with the episodes at some near future point