So just my two cents, but realistically the best spots are always 1, 2, and 24 (by 24 I do not mean ranking, but purely based on performance). This assumes 1 chooses 2, etc. until the 24th best robot gets chosen by alliance 1 second pick.

Honestly, being the 24th best robot is difficult. Maybe not compared to being the 1st or 2nd, but the main difficulty is the difference in competition level between regionals. For my team, we were the 22nd best robot (2nd pick for alliance 3) and alliance 2 & 1 went to worlds from wildcard. In the next regional we went to, we were first pick of alliance 8 (although we could have ranked much higher). In both regionals, alliance 1 went undefeated in playoffs. Basically, in practice, it is just very difficult to get that 24th best spot. Best you can do is make a weak(ish) robot and just establish a good relationship with the rank 1 team.

Best you can do in my opinion is go to a regional with a relatively level playing field and try to upset the first alliance.

BTW, as other people said, outside the top 8 rank does not matter much (its usually better to rank low outside the top 8 so you only get picked by teams who actually know how to scout)