The only way to unite the Republican party IS via President Trump. There is no "moving beyond Trump" because he is the only conservative who has shown he WILL fight, he WILL win, and he will never surrender. With very few exceptions, he is and will lead the party through at least 2024. So you should get over this idea that President Trump is going to fade away or step back...he's not. At a minimum, he will play kingmaker...and even that is far less likely than his being our 2024 candidate.
You keep running to the "Dems use him to justify cancel culture"...as well as all of their other ongoing efforts to subvert constitutional rule. And you're right...they do that. Where you're wrong, is that they will do it with or without Trump...in fact, without Trump as an impediment their efforts to overthrow the Republic will only accelerate. This is because they will ALWAYS find "justification"...that's what socio-fascists do. Too many conservatives like yourself seem to think if Republicans are just nicer and more PC, the Dems won't have anything with which to fuel their calls for radical socialism...but that's simply not true.
The Left hates President Trump NOT because he is obnoxious, populist, and ineffective....they hate him because he exposes who they are. THAT is what makes them crazy...and exposing them is the ONLY way to resist their destruction of the Republic. We cannot pretend they are just some normal extension of liberalism any more...they are not...they have left that behind somewhere in the late 90's. They are radicals, Trump calls them radicals. They are hypocrites, he calls them such. When they pull out the "ism" playback, he spits right back at them and calls them out for who they are...liars, hypocrites, and socio-fascists. THAT is why they hate the man and hate his supporters...because everyone else, with few exceptions, backs down and fears them.
The only really effective resistance left against this Fascistic tide IS President Trump and the few politicians (like Cruz, Paul and a few others) who stand up and actually fight. The rest, the NT's, have already surrendered...Bush, Kasich, Romney, Cheney, Ducey, Kinzinger, Sasse...all of that ilk have become, if not collaborators, certainly facilitators of this madness.
The hard core 5-10% like roamer are still genuinely opposed to this socio-fascist movement...but their demand for a perfect and pure conservatism makes them little more than useful idiots from the Left's perspective. They get mixed in with Q-anon and white supremacists...which is, admittedly, grossly unfair...and are thus discredited by much of the electorate.
Here is the bottom line, because Trump so enraged the Democrats/Marxists by exposing them, they are going to go whole hog, to try and impose their agenda in what will be a classic case of overreach. Gone is turning the heat up a little at a time, they've cranked the burner beneath the proverbial frog pot to max, and it will win them more enemies than friends. They are shrill, they are desperate, and they Know we know what they are. Trump or no Trump, that will not go away, and though they will blame him for that, it is their own actions that prove the theories they claim to be the stuff of paranoid fancy.