Trump had lousy lawyers; you educated me on that score with respect to the Administrative Practices Act. Surely Biden will have a creative way around the above.

Minor point - I don't think he had lousy lawyers. He was just a lousy President on that front. His lawyers lost on the APA not because they were bad lawyers, but because the Administration didn't bother doing what they needed to do in order to comply with those rules, and that came from the top. Trump wanted quick action and Executive Orders (and sometimes even announcing new policies via Twitter), rather than the many-months-long process of formal rule-making under the APA. Since he had no prior government experience, and little interest in adapting his own management style to the rules of federal government, he kept making that mistake over and over. The federal government doesn't work like a closely-held private business.

But he didn't lose these immigration cases on APA grounds (unlike the 'Muslim ban' cases). These, the Administration lost on the merits. The Immigration and Naturalization Act is pretty detailed, and Congress has directly spoken on most of these issues. They didn't leave the standard for a credible fear interview up to the discretion of the Executive - they wrote it into the statute. Same thing with "safe third country" measures; they wrote specific requirements into the statute that have to be met in order for that type of a system to be set up.

Biden can't circumvent those by being "creative" - again, he's already had his "safe third country" rule struck down by the courts as well. And I don't think he really thinks he can with these "new" proposals, either. Rather, I think the Administration has just concluded that there are political gains to the type of useless-but-performative measures that Trump took over and over again during his Administration. Immigration hawks like it when the Administration announces measures that are more restrictive, even if they're contrary to law and almost immediately stopped by the courts. The appearance of being aggressive towards immigrants is politically valuable, even if it doesn't do anything substantive.