Biggest barrier IMO is getting used to how the Controls are supposed to work (HBoxContainer/VBoxContainer/MarginContainer/...) and how the system encourages dee

Biggest barrier IMO is getting used to how the Controls are supposed to work (HBoxContainer/VBoxContainer/MarginContainer/...) and how the system encourages deep nesting, which you have to handle up front if you don't want any attached scripts to be full of long relative node paths. Once you have that down, and the flex-fill options, it's nice! Really!