Kowakujo EE - share your optimization tips!

Fellow EE enjoyers, please share your optimized EE tips and tricks!

I'm interested in these parts if you guys have any tips

• Painting #2, activating trap - are there only 2 locations for the ghost? (Jug/Wisp area) Is there a shortcut for this step?
• Flag step - is there an efficient way to determine which set of flags to combine first? i.e. start with the highest # first or something?
• Is upgrading the cat bomb worth it? can it be used in the boss fight effectively?

I'll mention some common ones -

• Check the fissure sites for the cat paws step
• Utilize Mr Peeks Field Upgrade to get the coin purse via Mystery Box.
• 3 Decoy noble step, there's a free max ammo nearby if needed.
• 3 Decoy noble step, there's a free nuke nearby that can be used after you damage the noble
• Lights out solver - https://dalms115.github.io/Scroll-Solver/
• Use the WW poison attack for the kitchen bowl soul box to get puffer fish (don't need brainrot)
• Use explosives in multiple points to turn harden lava back to flowing lava