There's no logic in Cedi. The Spurs already have Hernangomez and should be looking to draft their starting forward of the future.
Hopefully the Spurs find a good package for Poeltl. The value of non-star centers is capped pretty hard. If I were the Spurs, I'd absolutely not commit to having my starting five be a well-paid role-player. If they keep their heads up, they can find a quality center much closer to the time when they need one. Unless they think they'll be a solid playoff compe or next year (and for s sake, no they aren't just some internal growth from that right now; they'd be in the lottery again next year), they aren't going to be in a position to get value out of having Jakob on the roster.
Collins is intriguing. With Murray locked into the team for the foreseeable future, trading White is the only realistic way to break up the starting back-court duo that is going to cap the team's ceiling. If they can move him as the vast bulk of the value in a Collins trade, I can't say it would be bad. Of course, the Spurs could have just offer Collins a contract rather than go with McD and Zach, but that's in the past. Personally, if it's possible I'd rather the Spurs wait until the off-season to make a Collins trade. Murray and Collins aren't a contending duo. They'd still need a third star, beyond what Vassell or Primo can be expected to become. Hopefully, they'll find it through the draft, but even if they need to trade for that player, getting the highest 2022 draft pick possible is a key to that strategy. I think they're likely only a play-in team if they trade for Collins now, but even that could drop their pick immensely. Unless the Hawks need Thad or unless they're willing to take McDermott back, the Spurs should prefer holding off. Of course, if it's do or die, you deal with the lower pick.
Also, they should trade Johnson. He's not a serious starter on a team with a real rotation. Very few teams have a combo-forward-in-a-good-way needed to make him work defensively. Maybe he could go to a team like Boston in exchange for the draft capital the Spurs need to off-set a Collins trade. Boston is one of the rare teams that could use him, especially if they otherwise trade Brown. Ideally, I'd like the Spurs to run Murray, 2022 first, Vassell, Collins, Poeltl as the starting five next season, even if we all know the Spurs will send the guy to Austin.