Let's be real, JD Vance was picked by the party to be the adult in the room who can actually get Project 2025 passed under Trump since Trump doesn't care about Project 2025 and just wants what's best for himself at that moment and to be a petty little bitch
Also worth noting that Vance has no personality. When asked in Eau Claire, WI "why should a voter want to have a beer with you" he responded "uh I uh haha um I actually like beer haha" (he also tried to sidestep a question about Tim Walz by saying "we aren't talking about Minneapolis policy, were talking about Wisconsin" while literally standing 1 hour's drive from Minneapolis
And when asked "what makes you smile" instead of any sane answer he answered "insane questions from biased reporters like you!" Then followed it with waffling about how he loves his job so much while forcing the fakest smile you've ever seen
Fuck that's such an easy layup of a question too. You just respond, "because I'm buying". No positions to attack, potentially makes you look human, and maybe costs you a beer.
IMHO they want Vance for one reason: Trump thinks he can control him, but Vance's actual master, Theil, will have Vance 25th amendment the orange asshat on day one - giving Theil the whitehouse.
The Vice President can't do that without "a majority of either the principal officers of the executive departments or of such other body as Congress may by law provide" on their side. That can't happen without either the aid of people that Trump would have to select (and he's notorious for picking toadies) or Congress passing a bill to create a body to evict him.
Also the Ohio thing makes sense when you look at the Senate map.
There are exactly two remotely competitive races, Montana and Ohio. Ohio is leaning blue and Montana is leaning red.
Picking JD boosts Ohio and Trump is campaigning in Montana right now. Those choices were both made when Biden was still in so seemingly the idea was to secure the Senate and grab an extra seat or two so it's not razor tight and vulnerable to RINOs.