I expect Marc to sign for KTM unless he has a terrible year. Ducati management doesn't seem too keen on getting him on the official bike, plus the problem of his popularity in Italy. I'm sure they'll offer him a Pramac seat on moderate wages if he does well, which Marc's gonna reject probably. I'm sure he has in his mind a possibility of returning to Honda but not so soon.
I think that is what everyone expects tbh. Aprilia don;t seem interested (due to their own incompetence) and the sway that Marc seems to have with Red Bull (as we all know, they've terminated their Honda contract a year early because Marc is no longer there). The main curveball with KTM is Acosta. I'm still on the fence on how he will do this season.
The conundrum that faces KTM is the same that faces factory Ducati. If Marquez is competitive on the Gresini next yr, then he is a major threat if on a factory bike for 2025 so do you hire him to keep him from a rival? Gigi has said as much recently.
I'd also be hard pressed to see how the factory team justifies keeping their lineup if Marc beats one or more of them (I'm including Martin in this, as he is basically on a white factory bike). As you said, politics will likely come into play and Ducati have more than one cut off their nose to spite their face
Jorge will be promoted to the factory Duc if he repeats his performance. If not, KTM is a possibility if Marc doesn't go there, and just like Márquez he has already a shared history with KTM.
I think Jorge will look elsewhere next yr if he doesnt get the factory promotion. If Bastianini has a 2022 style season then it makes the decision harder. So many variables at present make this silly season an exciting prospect.
Fabio will most likely leave Yamaha unless left with no options. The probable options: Aprilia is the most sensible choice if Aleix retires, but also Aprilia is known to not want to spend too much money and Fabio would command high wages. Fabio could also choose to ride the Honda if they improve the bike sensibly and quickly, and Mir doesn't impress. Fabio could also do 'a Marc' and ride one of the satellite Ducs to prove his worth. And of course, there's the slim (IMO) chance the concessions help Yamaha a great deal and they manage to build a quick bike just in time to retain Quartararo, but it seeems the least likely of the options, they don't have much time.
The problem with the concessions, is they are reliant on teams using them. Cal Crutchlow has repeatedly said Yamaha haven't used him enough so I fear it will be more of the same story.
I doubt he will, but if Aleix follows through with his comment that this contract will be his last, then Aprilia have a vacant seat. Of course most say that Miguel would get that, but I think an option of getting Fabio would be silly to ignore. It's no guarantee that Mav will be retained either. He could decide to be a rev limiter tester again.
I think the general want from fans is Fabio on the Aprilia, and Marc on the KTM.
Also let's see what happens with the rumored VR46/Yamaha partnership. I expect some of the least favored riders to fight for factory Yamaha seats.
Maybe Mir will go to Yamaha if Quartararo leaves. It could also be tempting for Jorge Martin if he knows the door at Factory Ducati is closed.