One of the things I love about Pathfinder 2e (I am going to just refer to it as Pathfinder from now on, but want to frame) is how open party composition is. You really don't need to stick with the 'tank/healer/dps' composition. There are many reasons for this.
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(stat-wise, you don't lose much, since Wisdom is also tied to initiative)
In my games, I've found a 5th level party keeps itself up all day if they have 1 hour or more between fights.
For tanking and dps - a lot of optimizing for these roles is working with your party on positioning. How do we set each other up to maximizing our abilities?
Situational power.
Quick history lesson:
The 3.5 d20 era was defined IMO by how you incrementally accumulated advantages until your math was superior to the game's, rendering most situations moot.
You often won combat in the design phase.
It was very easy for you to make a character that was interesting but ineffective.
OK, history lesson over, back to Pathfinder!