Do you have a theory behind where you place everything in your hotbar

Mine is sort of theory, this is why

1. Sword, this is because sword has a few quick switches required. In addition, it usually is the one you start of with when using an attribute swap which is important (look at 4)

2. Axe, this is because it need to be near the sword to do an effective shield disarm.

3. Bow/breach mace, again breach mace needs an attribute swap with sword and since you don't want to change any of your other hotbars when you aren't using mace,

4. Mace. Even though mace could theoretically go as the 2nd place, I use the numbers on my keyboard to chance hotbars (1 - literally 1 on my hotbar). My index finger is the strongest and fastest and its very important to constantly execute stun slaming and add sharpness. In addition, it is usually easier for right hand players to have the swap for a hotbar to be more on the right then what you start at (e.g sword, start on exact left, then change to mace (4) goes more right). I find that effective.

5. Elytra (because when you fly down, you have to change to chestplate if u used rockets to mace, thus needing u tto access sword and mace)

6.Rockets ( because its right next to elytra and combinations are good if they are next to each other. It's also convenienty straight under the space bar which is used to start the flying method)

7 wind charge

8. enderpearl bc wind charge and enderpearl are combination and wind charge is still close to space bar which is used in mace pvp.

9. golden apple. it doesn't have a combination and its less important to switch fast bc i usually heal which I have half hp.

NOTE: This theory might not work for you, it just works for me.

Well those are decent hotbar configurations.

I usually use this. 1 elytra, 
2 mace, 
3 windcharges, 
4 gaps, 
5 sword, 
6 cobwebs, 
7 ender pearls, 
8 potions like strength or speed but sometimes I could go for more wind charges here, 
9 fireworks.

I do this:

1. sword

2. cobwebs

3. mace

4. ender pearls

5. elytra

6. rockets

7. gaps

8. wind charges

9. axe

in bedwars i normally use

1. sword

2.gaps

3.blocks

4. more blocks/tnt

5. tnt/ fire charge

6. bedbugs

7. idk

8. idk

9. idk

i dont play that much normal minecraft i play more bedwars

Are we talking pvp or survival?

Anything really.

Yes, for PvP, I agree with axe near sword for shield disarming. I think that's important

rdfg movement

z1 totem

s2 obsidian

a3 anchor

w4 pearls

v5 gapple

b6 utility

h7 glowstone

y8 crystal

t9 sword

e open inventory

3 drop item

spacebar jump

shift crouch

n toggle perspective

I think these were my hotkeys

The main reason was because I was a crystal main, so I needed to be able to switch between hotkeys extremely quickly, and one of the best ways to do that is to have your hotkeys spread out so you don’t have to use the same finger to press them

I think there is no need to overthink it. You can access everything with just a key, and if on console or scroll, I try to make important things close together. That’s it

my hotkeys arent to crazy, just listing the things that i changed

1,2,3,4,5,6,r,g,b for hotkeys

c for zoom

mouse button 5 for f5

i have a REALLY big keyboard so i kind of struggled with the 7 8 and 9 keys so i made them closer to my resting location of my left hand

mouse button just because i wanted to use it and also same issue with it being too far away

anyways thats all i have to say

Not exactly a theory but...

I'm a leftie so Mouse in the left, control keys are O, K, L, and ; , and obviously left hand on the actual monitor. Also, doesn't matter if I'm PvPing or playing solo. Always the same arrangement.

1. Food. For starter worlds bread usually, but later golden carrots/gapples. I also seem to have a knack for finding Notch apples, so sometimes those too.

2. Hotkey: O. Sword. This is so in battles I can get from my sword to food quickly.

3. Elytra/Chestplate. Allows for quick access since I do a lot of elytra PvP

4. Generally nothing cause I like a space to have a free hand. I might have a mace, but I usually only get them for clout, not to actually use. Spears are the only thing needed to stop them now.

5. Hotkey: I/i. Depends on the world, but normally multi-shot rocket launcher, or sometimes loyalty trident.

6. Hotkey: ' . Ender pearls if I have them. If not, always Rockets.

7. Hotkey: J. Always a package, always diamond instead of netherite. Ihdk why I always carry one, but I do.

8. Hotkey: P. Axe. I sometimes switch the pickaxe and axe tho and it's gets very confusing in battles.

9. Depends. If in a solo world, lodestone compass to my base. If a PvP situation, some sort of pot(I like strength there usually, but I'm all the kind of weirdo that keeps slow falling and invis pots on hand no matter the situation.

I like to keep my most used things in the front(Food, sword, Eytra, Multi-shot. The exception is the rockets), Things I could survive without in 5 and 9, and other things I don't feel comfortable without in 7-8.