Agree with most of this. Overall UI needs some spit and polish.
8. Unclear how I should coat weapons using poison bottles etc. Why the hell would I want to drink the poison!?
There are a couple of different types of poisons:
1) Dipping kind, click dip and then click on these in your hotbar to apply
2) The ones that warn you not to drink. These you throw at enemies to poison them. I usually save these for the bosses. Found this out by accident as the UI certainly doesn't give you the prompt that it's really a missile weapon.