Your other option is to apply for an F1 student visa and enroll as a full-time student. If you have money and decent academic profile then this is one of the last route to extend your stay, take classes in fall and spring, intern in summer (and if possible, in spring too while taking classes if the company/startup is based locally), and try to graduate in 1 or 1.5 years and then apply for OPT and find a job.

If you're applying for a PhD, chances are that you will get a nice RA position and everything will be covered..You can always leave your academics if you get a job after a year -- which might look extremely bad on you but it's you first and then comes the rest of the world. You can always take part-time classes after you get a job to make up to them.

J-1 visas with minimum residency requirements have something like "Two year rule does apply" written in the passport. People who come sponsored by program like Muskie have that limitation