There was far less content in Heavensward than in Endwalker

[Jeeqbit]

Ridorana's Construct 7 prime number mechanic. (You can even extend it to make a Sudoku-like mechanic)
Staggering CCs so that different orbs resolve their raidwide damage at different times (A6S, A8S, and arguably E8S)
Mini maze mechanic but done in a more engaging way than just get to the endpoint (O3N)
Dragging adds under AoEs to resolve mechanics (like Xelphatol but at a Savage level), think of a volcano eruption that you exploit to kill ice sprites.
etc.

I see, good ideas.

I feel this explains it better than just saying to make something other than "in, out, stack, spread". I think this would be good feedback (if they actually would read the English forums ).