Long Knives: no, as we have seen since trump 1, there is no one else which is able to mobilize maga the same as trump, no inner-party split or second leader. desantis was making a play for it but ofc fell apart

Not to say trump won’t go after anyone deemed a threat, he is definitely petty enough to do so, but it won’t be as drastic

As for reichstag I am not sure, on one hand the Dems aren’t really opposing him so there’s no reason to, on the other hand they aren’t opposing him, so he might actually go for it. Heritage foundation would be happy, but it would probably upset business interests (assuming stock market goes down)