This is a special topic related to things that players don't like about Dynamic Surroundings. Intent is to gather info on things that can be improved, or even cut from the mod. Suggestions should be filed as separate issues in the tracker; however, please make sure it hasn't been suggested before. :)

I'd prefer if I could tell the armor render on the HUD to be above Botania's flight bar, instead of the other way around- that or have the armor toughness gauge always showing when empty. Botania's armors do not add armor toughness so a full terrasteel suit and flugel tiara result in an empty space when wearing the tiara.

Not sure what you are referring to. Dynamic Surroundings doesn't touch those HUD elements.

The Armor Toughness HUD normally shows up exactly where Botania's flight bar shows up. There is no way to tell the Armor Toughness HUD to be somewhere else, only a way to tell Botania's flight bar to be somewhere else. So that's the solution I went with. A screenshot will hopefully demonstrate why this solution isn't ideal for Botania players.
A player with Thaumcraft's endgame armor will see something like this wearing a Flugel Tiara: https://cdn.discordapp.com/attachments/589856940964708353/666787512122998797/2020-01-14_18.35.03.png
That looks okay. This is what full Terrasteel Armor looks like however:
https://cdn.discordapp.com/attachments/220566945290780677/667003851957731349/2020-01-15_08.54.29.png

How'd I confuse those renders with your mod? It's Rustic that adds them.