Because...

For most of us, it is the one Sentai season that we watched, LOVED, and wished would never end.

Not true, as long as they are making "new" sentai series. They'd always have new keys to get.

And I ask "Why?"
This is coming from the perspective of someone who disliked Gokaiger, so I'm curious what about the series would make it worth continuing beyond it's conclusion (Which was already a good finale).
As the phrase goes, all good things must come to an end. I can cite points where people who watched and loved Simpsons now wish it would end. I watched and completely adored Gekiranger, but I knew that I had to let it free.

And Gimmicks end. Ranger Keys and Ranger Batteries will soon fall to the wayside of the next big collector's gimmick.

And I gave you the answer to your "Why?"

If you didn't like Gokaiger then you wouldn't understand the "Why."

I could happily live in a world without Go-Busters or Kyoryuger. Just sayin'.

"I love it"
"Why?"
"Because I loved it"

That's what the conversation boiled down to. You answered fuck all.

And you need to chill out. If someone is connected to a series and truly enjoys it but can't articulate why, that doesn't invalidate their point. It just means they aren't sure how to put into words why they enjoyed something. It's the same reason people know someone is their soul mate, or think a sunrise is beautiful, or that they like a particular dish of food even, etc etc. If you can't articulate it, it doesn't make what you experience any less valid.

Now for me? The one show I didn't want to end? Gaoranger :( I always felt there was more to tell.

Fine. Fine.

I might get some hate for this but my opinion I wished Shinkenger never ended like if it went on explaining more of the past Shibas and what not.

Runner up is GOOOOOOOKAIIGEEEEERRRR.
Gokaiger had a nice gimmick(which the American keys have done nicely since I can't stop flipping them) and the suits, me has we're all nice. Now if it continued I would of liked to see more Megazords and see more of Aka red.

To be honest Dino Samba hasn't caught my interest lately, like the show slowed down quite a bit, and I think I'm a bit behind, by like two weeks.

Check out my reasoning on page 2.

I just thought the cast and characters were awesome. Even if the villains (other than Basco) were weak.

And I'd like to see more of them, partly because they sometimes got the short shrift as the series focused so many of the episodes on past sentai teams instead of the leads.

Gaoranger.

So many Power Animals, so little time...