Skin creation
Riot seems to be cutting back their production on pretty much everything lately. We no longer get a bunch of skins per patch and almost every skin released seems to be connected with some sort of event, resulting in less original and stereotypical skins.
I want Riot artists to show more more creativity when it comes to skin design and not just go with the easiest and obvious themes. I also wish there were more skins released for various champions.
Another thing I noticed is that model designers really don't pay much attention to details. Skins look bland ingame. Color mismatches are almost a staple on latest releases. Usually community makes an uproar on such problems but unless it's a Diana or Leona skin they go overlooked.
If Diana wasn't designed by IronStylus her Lunar goddess skin would be released in her poor original form, just look at Snowstorm Sivir. If slower production was supposed to be the result of higher quality work then I don't think it shows.