I'd be leery of taking the Ar 234 far out to sea with those engines. With them conking out every 10-25 hours, odds are one of them would blow during a long range patrol.
Also, it's more of a bomber than a fighter. As a bomber intruder, it has pretty good potential. As you note, the payload and speed will make it something like the Mosquito. Almost impossible to intercept during the day and even worse at night.
Still, those engines are a problem.