Jake as green doesn't make any sense. Doc (the Green Ranger in Gokaiger, the show that this is based on) was a goofy, inexperienced character, and that showed in his fighting style. Jake is a more serious character, and he has been shown to be pretty competent at fighting. It is going to look really weird to see him suddenly flailing around like he doesn't know what he is doing.
Noah is a less experienced and less confident character. He WILL NOT FIT as the blue ranger. Joe (the Blue Ranger in Gokaiger) was an experienced ex-military combat specialist. Noah couldn't even lift Jake's axe in Megaforce. Now we are supposed to believe that he is a master swordsman, and the strongest one on the team?
They should have just switched the roles. Jake should have been the Blue Super Mega Ranger, and Noah should have been Green. They've done it before - in Power Rangers: Turbo, T.J. was the Red Ranger. Then they switched him to Blue Ranger in Power Rangers in Space.