My thinking is along these same lines. Seal the border, step one of any reasonable plan. Step two, remove the economic advantage the illegal worker has. I am sure the illegal problem differs depending on where you live. In the midwest, the illegals are taking work for half the pay because they are being paid in cash and don't get half their pay confiscated. Contributing to this is the graduated income tax code. Like you, I think MANY illegals would self-deport if we implemented an NRST.
Guest worker plans and making illegals felons neither one address to root cause.
The "root cause" is that "our" leaders -- and, the "interests" that own "our" leaders (lobbyists paying legislators for continued access to cheap labor, "motor-voter" constituents, etc.) -- want the illegals to continue the invasion.
The problem is that "the problem" is not perceived as a "problem" by those who are calling the shots.
Oh, sure, we make noise, and they pump sunshine up... up where it really shouldn't be, and at the end of the day, it's business as usual.