Voters can no longer place a petitioned warrant article on the ballot with 25 signatures unless it is an article that appropriates money. Other petitioned articles will require a much heavier investment in signatures and time.

It is true the Charter will only allow petitioned articles at the Deliberative session for appropriation related articles. This is a change.
But, it is also true that in our current form of government, only the appropriation articles are binding on the Board of Selectmen. Most any other article you could submit is not necessarily binding. Quite a few of the recent petitioned articles have been determined by the BOS and their legal council as "advisory" only. Some of those advisory articles have been adhered to, many have not. I would be happy to list examples if you would like me to.
So, do you really loose power with the Charter? I contend you loose the illusion of power since you can no longer submit "advisory" petitioned articles. The Charter makes it black and illusion, no chance for it being ignored, and no reinterpretation by the current governing board.