I agree with Connor91. In fact when I wrote my ToUP review I got to the end of it and realised I had forgot to mention my impressions of Arthur/Gwen, and then realised I didn't really know what to say about it. They were still holding hands, gazing into each others eyes (which they do very well) and she was telling him she trusts him more than Uther. It made so little impression on me I forgot to remember that this was Arthur/Gwen a year on. There was absolutely no sense of time having passed, no sense of the things they had shared in the intervening time.
When you look at the Arthur Merlin scenes, to some degree they were still up to the same old double act -- Merlin teasing Arthur and Arthur bullying Merlin. But there was much more of a sense of practiced familiarity there, and Merlin had progressed from cowtowed underling to mouthy and confrontational, clearly used to getting his own back, even in front of the knights. So whatever your personal opinion about the persistence of Bully!Arthur as a character trait, at least there was a sense of progression there.
I think they might have found a similar perspective on the Arthur Gwen relationship, but there just never seems to be that much thought put into it. It makes you think that when they were writing up the Bible for this show, under Guinevere it just says: Arthur's future Queen but loves Lancelot -- and their scenes are a replay of, "I like you but there's something in the way of our love." Just over and over again. It gets really tiring. I think my brain just shuts down after a while because it's not getting any new input.
It also occurs to me that every time someone tells Arthur, "I trust you more than Uther" or "When you are King, things will be different," it means they are basically looking forward to a time when Arthur loses his father somehow. And Arthur is clearly a boy who loves his Dad, so it's no wonder that these well-meant assurances just make Arthur feel uncomfortable and he resists the idea with all his heart.