The only long dresses for Eve would be avatar clothings, just like Exotic's job avatar set. You could easily buy some NX Cash to get one, or like Drone mentioned you could save up ED and try to find the Arch Angel set. Depending on which piece and character they range from 7mil to 25mil. Hair is another story, ranging from 30mil to 110mil. (Eve's being highest in demand, stay on the higher segment of the price range)
The Arch Angel set is old and limited edition now. They've gotten cheaper, but it's almost near impossible to find every piece (namely, hair) in the market nowadays. I spent 200mil to complete the set.
As for the other three potion slots, you need cash to have access to them. The cash item for that is not released yet, however.