“If he can wipe immigration laws off the books with his signature he can cancel the next election with his signature”
Not really.
Just take a poll of American voters and ask the question: “Would you support the President of the United States suspending elections and taking away your ability to elect your leaders?”.
His attempting such a thing would be overwhelmingly condemned by almost every voter across the American political landscape, probably to the tune of at least 98% of the electorate. He would be impeached forthwith and convicted by even a Democrat-majority Senate.
Why suspend the election, when he can manipulate it? Much easier, the Kremlin did it very well indeed. He really has no desire to remain President, 0 is just a revolutionary operative.