I dont think that messages/petitions or sitout protest will change much. In my opinion players that are interested in saving/improving poker environment should try to realize that the reason of this instability goes with ps as monopoly. There is no real alternative to choose.
The question is how to make this alternative?
Sign a letter and send it to Scheinberg asking him to build a reliable company once again?
Poker economy is slow dying economy everyone knows that, so its kinda hard to find just a person with money willing to invest. However if you have skills and a vision on how things work in poker, it might fire away.
Accept players from all countries as well as all that ****ty payment methods, start with very aggressive marketing with an opportunity to pay some portion of players deposits to those who attract these players (so in every ****hole of this planet people would be able to deposit/withdraw/play) and with solid reputation it might work.
From players side cooperation is the key.