well u have to see the other side: i play with a lvl9 on ptr i would never have a chance against tanks like yours without such strong towers and if u wanna destroy a tower u can make dynamite
the exp-rate is lower because it was to high the last time ptr was open, it doesnt make sense if everyone is lvl25 within a week
i think its good as it is now, maybe the rate of producing ressources could be a bit higher. and i think we dont need exp to let all players hunt each other down. i saw it yesterday 10 players waited for a piece of coal so there was enough war even without exp^^