New Client Needs Item Sets
I love almost everything about the new client and I think Riot did a really good job. One thing is missing though... the item sets are gone. You'd expect that Riot put them under "Collection" which is where it would make sense to put the "Item Sets" tab but it simply is not there.
Please add item sets to the new client before you remove the old client forever. It's nice to have in-game so you can purchase stuff faster but potentially even more importantly, some people (including myself) have an extremely large number of hours of theory crafting in those item sets.