Next hextech skin, and their general value

So i recently got 10 gemstones, and to be fair i dont really like the hextech skins that are currently available. They're lacking too much compared to other insane legendary skins that you can get. Since it take forever to get 10 gemstones i feel like these skins should have more flavour to them than they have. For instance Project: Vayne vs. Soulstealer Vayne, if you just look at the animations and the particle effects, Project: Vayne is way more refined and appealing. The same goes for Dunkmaster Darius and Dreadnova Darius in my humble opinion. Further i'd like to know if we have any insider info, from anywhere, to what the next upcomming hextech skin should be? Personally i'd like to see something like zac, since all of his skins are basically just chromas at this point. Maybe just the most picked champion in higher elo througout the season? I dunno man. As a main, i wouldnt mind seeing something like Shyvana, nocturne, bard, janna or leona as well :3 What are your thoughts on this guys? I've added a poll, for the 10 most picked champions in S8 for professional tournaments, so far, to let riot know what the community wants :3 (Link to these, as of 2/4/2018)