A few of these are going to be reiterations of some things I've said before around here but I'm gonna put 'em all in one place.

Character Select Screen
It would be nice to be able to change the order of your characters on this screen. Currently it just defaults them to whatever order you made them in. The biggest reason this is desirable to me currently is that it doesn't default selection to the last character you played. That would be a nice change, as well as it defaulting to the last difficulty that character played on just so you can get into game faster.

Keybinds
I've suggested this one before but I am very used to a very specific keybinding set up and it would be really nice to be able to choose whatever keybinds you wanted, especially for your action bars.

Tooltips
I would personally love to have more detailed tooltips, especially pertaining to buffs on yourself and debuffs currently on yourself and enemies. Also, it would be nice to have a buff tooltip pop up for weapon procs, especially ones like Celestial Tranquility from Fists of Qiromir. This could alleviate a lot of "What does "whatever" weapon proc do?" questions.

The Item Level Floor
This could maybe use a buff, or perhaps tweaking. In some ways it's cool to be able to get lower level items for alts and stuff but sometimes it can be really frustrating to get a level 14 unique from a level 99 RARE mob. Also, as a request can we have some transparency with drop tables? Can we see a list of what items only drop from 95+ mobs, or even a list of every item and it's base mob drop level? Also, do different sections of mobs in a quest have different drop tables, or even mobs in different zones, regardless of level? I.E. do Deranged Gorillas have a higher than normal chance to drop Gorilla-Hide Boots?

Champion Affixes/Traits
I feel like the Durability Affixes in particular could use a once over. Usually, a mob living for nearly a full minute simply because you hit him 99% softer than other mobs is generally more annoying than challenging or interesting. Getting Tough, Jugg, Resistant to your main damage source who then pops Sanctuary, Barrier, etc is really just not fun. If this were D3 these would be the elites you'd just skip.

I'll have more for later but this is plenty for right now. As always, thank you for your hard work and dedication, Mael

One that stands out in my mind is the character select screen. That wouldn't be too hard to address and it would really boost QoL.