[Q] What should be my first considerations in starting an E-2/E-1 case?

First, you should study this site to find out which visa among E-2, E-1 and L-1 is most suitable for you? In addition, without your realizing it, you may already be eligible for EB-1 multinational executive/manager immigrant category if you have a company in your home country and an "affiliated" company in the U.S. Or an EB-5 case might be suit you the best.

Second, you should lay out a brief plan on the steps you have to take and then find out as much information possible on executing such plan.

Third, you may wish to consult an immigration attorney about aspects of U.S. immigration law which you do not have clear answers on.

Fourth, you may wish to retain a professional to find a suitable E-2 enterprise business if you decide to pursue an E-2 visa or status.