I just love how good the mecha looks like in-suit.

to me, it looks like an Exosuit (and not the type like Bull Taurus, which could work for me)

Why is Blue making an Ultraman-ish hand pose??

Confirmed! Blue is Ultraman!

While many people focusing on the plot, me: THE GUN!
The weird color scheme (Yellow + Blue, like Beast's Hyper Form), modeled after frog? Definitely unique but for me it'll take time to be accepted like previous Sentai's Gun

Toad to be exact. Gama is Japanese for toad. Frog is "kaeru". Like I said before somewhere, it has to do with the Jiraiya lore and which is why Ninjablack Jiraiya in Kakuranger had a toad for a robot.

Two things come to mind from these images;

1: KiNinja's pose looks like he's trying to get a ride after stubbing his toe xD
2: MomoNinja looks like she's skilled in martial arts?