Do you think they'll ever allow us to change teams

Probably not.

I think you can contact them and they will let you change teams once. I've never tried to, but if you don't try, you don't know.

Do you think they will ever allow us to change Pokemon moves?

Some may label you a cheater for using a 3rd party site to scan gyms.

Some may say why would you need to change teams because Mystic is in all the gyms.

But IMO you shouldn't need to change teams, just find another hunting area. All gyms in my area a Valor. I travel outside of my area to where I can find gyms of my own team and prestige and stay in there for a while. Or I go to gyms that require admission fees or secluded areas that don't get lots of foot traffic. Ive had defenders sitting in gyms for over 3 months now but they would never last a single hour if they were in the city.

Find where the mystic gyms are and place your defenders there.

Most likely not, especially if the reason is so you can switch to the dominating team

Complete opposite in my area. Mystic dominates for miles here.

Where do you live at??? my area is 90% mystic/8% valor and 2% instinct and i live in NYC.....

If you're lower level and are willing to, you can restart on Mystic...

Getting to 25 or so should be less than a month perhaps, esp now with even more new pokemon...

Like others have said, you need to find Mystic areas as they are supposedly the most "popular" team in terms of numbers.

This is from Niantic Support URL

"How do I change my team?
At this time, it is not possible to change your team."

I think maybe in the future it will be possible able to do via cash item or something like that. Anyway, its the same situation here in my town, tons of red and blue players and im the only yellow. In fact, today i ran out of items to fight gyms, 0 potions and 0 crystals.