Other than Biden personally, maybe direct the ire on the acting head of OMB or other senior staffers, or even call the office directly and hit them with a coordinated phone, email, or even snail mail campaign.
My point on the arguments still going on over the election is that, maybe instead of conducting a circular firing squad, how about we instead concentrate our ire on the idiot in the Oval Office and his various shenanigans, as opposed to arguing over whether someone is secretly a Democrat/I sufficiently loyal to Trump/a RINO/etc? Seems like a far more productive thing to bring this to the public’s attention and erode his support.
The office number is 1-202-395-3080, but I think if a right-wing phone or mail campaign is going to have an effect it's going to have to find weak points.
The only thing worse than a circular firing squad from my perspective is a regular firing squad where I'm against the wall. You haven't outright stated but IMO in a few posts you've implied that you think that MAGA/populists etc. are more prone to trying to purge moderates. I recognize I have a dog in this fight, but in my experience it's the opposite that's more frequent. Moderates and extremists in alliance is a powerful dynamic- there's a lot of that on the left, and it's worked well for them. But it's got to be both ways.
On the RINO Q- Part of opposing Biden is necessarily going to be framing the issues and arguing for an alternative. As a nationalist, I don't think ConInc can effectively oppose Biden. For one thing, I don't think there messaging or framing is at all appealing. I don't want our side to be arguing, "Biden's a socialist!" I want our side to be arguing "We wanted to give you $2000, now Biden isn't even giving you the $1400 he owes you." For another, there's been some just plain incompetence on the part of the GOP establishment leadership. For instance, McConnell backed McSally for the 2018 senate seat in Arizona, which she lost, then lobbied for her appointment to the other Arizona senate seat which she subsequently lost.
Additionally, this isn't really the public. It's publicly accessible, sure, but this isn't social media where people can get something trending and so get it exposed to a much wider audience. There isn't really any support for Biden here, so issues that are actually disputed by the people here are necessarily going to get more debate.