That's fine :-) It ties in with what I commented above, i.e. conspiracists first assuming that disagreement must be culpable malice.
I already answered #3: the true rejection seems to be not "you are editing about us on Wikipedia to advance RationalWiki at our expense" (which is a complicated and not very plausible claim that would need all its parts demonstrated), but "you are editing about us in a way we don't like".
Someone from the IEET tried to seriously claim (COI Noticeboard and all) that I shouldn't comment on the deletion nomination for their article - I didn't even nominate it, just commented - on the basis that IEET is a 501(c)3 and RationalWiki is also a 501(c)3 and therefore in sufficiently direct competition that this would be a Wikipedia COI. It's generally a bad and terrible claim and it's blitheringly obvious to any experienced Wikipedia editor that it's stretching for an excuse.
Variations on #3 are a perennial of cranks of all sorts who don't want a skeptical editor writing about them at Wikipedia, and will first attempt not to engage with the issues and sources, but to stop the editor from writing about them. (My favourite personal example is this Sorcha Faal fan who revealed I was editing as an NSA shill.) So it should really be considered an example of the crackpot offer, and if you find yourself thinking it then it would be worth thinking again.
(No, I don't know why cranks keep thinking implausible claims of COI are a slam dunk move to neutralise the hated outgroup. I hypothesise a tendency to conspiracist thinking, and first assuming malfeasance as an explanation for disagreement. So if you find yourself doing that, it's another one to watch out for.)
despite hearing that one a lot at Rationalwiki, it turns out the big Soros bucks are thinner on the ground than many a valiant truthseeker thinks
(More generally as a Wikipedia editor I find myself perennially amazed at advocates for some minor cause who seem to seriously think that Wikipedia articles on their minor cause should only be edited by advocates, and that all edits by people who aren't advocates must somehow be wrong and bad and against the rules. Even though the relevant rules are (a) quite simple conceptually (b) say nothing of the sort. You'd almost think they don't have the slightest understanding of what Wikipedia is about, and only cared about advocating their cause and bugger the encyclopedia.)
This isn't what "conflict of interest" means at Wikipedia. You probably want to review WP:COI, and I mean "review" it in a manner where you try to understand what it's getting at rather than looking for loopholes that you think will let you do the antisocial thing you're contemplating. Your posited approach is the same one that didn't work for the cryptocurrency advocates either. (And "RationalWiki is a competing website therefore his edits must be COI" has failed for many cranks, because it's trivially obvious that their true rejection is that I edited at all and disagreed with them, much as that's your true rejection.) Being an advocate who's written a post specifically setting out a plan, your comment above would, in any serious Wikipedia dispute on the topic, be prima facie evidence that you were attempting to brigade Wikipedia for the benefit of your own conflict of interest. But, y'know, knock yourself out in the best of faith, we're writing an encyclopedia here after all and every bit helps. HTH!
If you really want to make the article better, the guideline you want to take to heart is WP:RS, and a whacking dose of WP:NOR. Advocacy editing like you've just mapped out a detailed plan for is a good way to get reverted, and blocked if you persist.