I uniquely played through the game with savestate abuse to see what the run would be like. I also watched some player's video. I learned several things.
Genova:
First you should beat attendants in order to make the animation of power up shorter.
Booskaboo and Flammie:
Use downarrow key.
Desert and Snowfield:
Whichever you first go, you should go through both places at night. It takes a while to beat enemies. Use dreamsee herb, take a rest at inn or plan to get there at night.
When you set up glitched Kevin, taking damage isn’t necessary.
When glitched Kevin gains his lvl in wolf form, he temporarily loses his glitched power until screen transition or using a dreamsee herb. You should avoid his lvl up in mandatory fights where you can’t run away.
If you take Duran, you can buy equipments at Pedan except for Kevin w/o losing glitched Kevin.
GBs:
I beat in order of Wind, Moon, Light, Earth, Wood, Ice and Fire by reference to RaneofSoTN’s order. It looks good. I used a dreamsee herb at Tree Sea of Wonder. I reached Pedan in daytime.
Maybe Xan Bie should have been beaten earlier. I couldn’t defeat him before his fire ball.
After you beat Doran you cannot use wind drum where you appear, where you fight against Lugar. You have to plan in order not to gain Kevin’s lvl after you beat him.
At the battle against Mispolm running away from tentacle might be the fastest way. To do so, you can avoid their magic and special attack.
Getting papa poto's claw from papa poto was a little difficult. It took no less than 200 frames. He also drops ??? seed, puipui grass and poto oil so getting from silver knight would be easier and faster.
It seems possible to be invincible against physical attacks w/o L/R according to
around 1:40 of this video by Beastly242.
Count of the Evil Eye and Beautiful Beast have Earth as their common weakness. Though the animation of diamond sabre is longer than that of other sabres, you can save item inventory.
When you beat the first great demon and check the first skull switch at dark castle, you can shortcut with magical ropes. The number of magical ropes you have to buy is four, though I’ve not checked it firsthand. I checked it via debug room. I played through Carlie’s quest.
I didn't mean to go on so long but I hope it would be helpful.