I did not like how you had to click multiple times to get access to something. It has separate tabs for
everything. I prefer as much as possible to be visible with one click, like how you have your stats, inventory, magic and maps are all visible at once in Morrowind. And the journal could be popped up at any time with J. Also on the fly all the menu parts could be resized, moved around or be kept on your screen while playing. That was nice.
And the inventory font was too big, you couldn't see many items in your inventory at once. Thankfully UI mods managed to fix this.
What I did like was the quest sorting, it was easy to find your current quests and your completed quests. Morrowind's journal system got a bit more organized with the Tribunal expansion, but it can still be a bit confusing.