If Trump wanted a bulldog on the ticket then he got one. However, having 2 bulldogs may well be a bit too much. Not all Trump followers believe the government has to be destroyed and rebuilt.
J.D. Vance is a man who believes that the current government is so corrupt that
radical, even authoritarian steps, are justified in response. He sees himself as the avatar of America’s virtuous people, whose political enemies are interlopers scarcely worthy of respect. Apparently not many people agree with him. His polling numbers are far behind Trump and worse than any VP candidate since 2000.
If Trump really wants to destroy democracy in America and has full control of congress, then Vance is probably the man he needs in the VP slot. However, I don't think that is likely. What he will need is a VP that can cross the isle and negotiate. That man is not Vance. Pence's primary job was putting out Trump fires. Vance will only add more fuel to them.