For anyone struggling with relics:
High Road:
https://youtu.be/nvxiS1_Qm0Y
This route uses the ropes as little as possible, just three quick jumps (and the third might not have been necessary).
The turtle you flip and then bounce off is a lot easier if you do a small bounce first, then just hold up/x as soon as you're in mid air.
Some of the jumps were I don't use the turtle have to be pretty much frame perfect. I found these easier if I spin just before, not sure if that actually makes a difference. You might prefer to use the ropes instead (especially the bridge right after Aku Aku).
The Lab:
https://youtu.be/8gW0nGMXydI
Probably only useful if you want the platinum time, although it does show how to cheese the second to last room.
The twitchy movements I do at the beginning are to slow me down enough to pass through the first set of lasers, this sets up the timing for the whole level.
Most of the enemies I kill I'm hitting forward to destroy specific objects further in the level.
The last room might be faster to use the sides instead of the TNT boxes, not sure.
This run was only 0.5 seconds clear of platinum, it's a really tight time to beat.
I didn't save any others ¯\_(ツ

_/¯ but these were the hardest. Generator Room is also quite tight with its platinum time. Sunset isn't so hard it's just fucking long, and Native Fortress is the RNG bullshit run.