Part of Republican National Convention will be held in Jacksonville (UPDATE: No it won't)

[Del Tachi]

City councils would have to want and approve the moved convention. So you can cross out many cities in Florida, Georgia and Texas just based on that.

Nah.  There're these things called State Troopers that Kemp and DeSantis can easily dispatch to overrun APD or whatever.  Security for national conventions is never a strictly local undertaking, anyway.  State governments are unitary, governors can overrule mayors or city councils by simple order and they hold all the keys to enforcement (which should be entirely evident, given that it's Governor Cooper who's threatening to cancel the RNC and not the mayor of Charlotte). 

[Del Tachi]

Conventions are just giant, drunken soirées for party insiders. A night full of joviality and revelries while they go through the motions on symbolic delegate apportionment and the routine commitment to their principles through the platform. It’s a highly nominal affair that lost its substantive purpose awhile ago, so they have basically no effect on election results in the state.

TBF, even if conventions weren't nominal affairs I'm still not convinced they would have any effect on the outcomes in the host states.  Conventions have always been more of a media event rather than a local campaign event.