Well since you said you wont be getting anbu itachi it means you are playing on a rly recent server so you looking for a ninja to dominate the server from beggining?

If thats the case and right now you only willing to spend for 1 event ninja i would say dont go for kisame since he works better in specific teams to be able to truly shine.

Shisui is easy to build a team for, specially in an early stage of the server. He brings alot to the table with his buff and shild removal, which should work rly well against early lvl root of warrior teams, a dodge and ignition so a well rounded kit.

Deidara is damage beast. Aoe standard with ignition. The best team for him without any other event ninjas is earth main with double standard mystery, sailor sakura for aoe damage and heals and jigokudo for the chakra you need and also heals. And that is a team that can stay meta for a long long time.

Regarding minato, hokage version is better, he scales to a ridiculous point where he can murder your team alone and dont worry about the fact he doesnt have a chase, he deals enough dmg already and while jonin version need to chase to scale, hokage has a sure scale with the passive.

Overall i think i would personally go for deidara but i recommend choosing between deidara and shisui since kage minato is harder to get because he shows up way less in events.