My thoughts on new runes
Sorcery - underwhelming as a whole for most traditional mages because most of the runes are really gimmicky. On top of that they were concerned with giving them counterplay to the point it doesn't make the champions feel good in many scenarios. The tree as a primary is good for DoTs and supports because of Aery, and for Cassio and TF because of Phase Rush (and Ultimate Hat), but it's largely weaker for standard DPS mids because you're relying on scaling AP which is meager and no mpen to punch through targets. Assassin tree with sorcery as a secondary is usually much better since the only things you'll usually need are Nullifying Orb, Ultimate Hat, Transcendence, or Scorch. I think a few things that need to happen are making Manaflow Band have a much shorter CD, since 5 points in Meditation could regenerate roughly double that, and it was passive power (active power should be stronger than passive power). FInally, I think Gathering Storm and Waterwalking could do with a little extra power since Waterwalking is so damn niche and Gathering Storm is just not that good for what it does. Giving up the extra damage from Scorch for 8 AP @ 10, 24 @20, etc. just isn't worth it.
Resolve - I think a lot of this is super beneficial to supporty tanks but not standalone tanks. Standalone tanks meaning any tank who derives their value from disruption and raw tankiness over being Braum. Resistance as a rune slot is part of this issue, unless you can get enough HP regen going to keep their passives turned on for the remainder of the game. If there's any OP runes here it's Demolish. Shit's absurd.
Precision - Pretty solid. Part of the reason is because it's just a ton of raw combat stats (minus Heroism), so it's hard for the super niche trees and runes to compete. 10-12% damage increase on combat, 3% -> 18% AS for bounty hunter kills, and both Press the Attack and Lethal Tempo are really strong. Fleet Footwork could be better but I think the tree needs to be toned down in general (or others buffed) before making changes.
Domination - Ridiculous. Electrocute makes TLD blush. Tracking is neat but it's rarely used if Domination is a secondary key unless you're going for the Eyeballs. Cheap Shot kinda blows on all but a few mages who can't make use of the rest of the tree. Dark Harvest is pretty solid. The tree in general is fucking amazing for assassins, especially because of Sudden Impact. This, combined with Press the Attack have made Lucian relevant again in solo queue which is how you know maybe it needs nerfs. Kassadin w/ Scorch and Corrupting Pot is probably one of the best midlaners so long as Zed is banned.
Inspiration - super niche and it's probably the contender for third strongest book imo (behind Domination and Precision, respectively), and it's almost entirely for Keystones. Kleptomancy earns an ungodly amount of gold, so I've seen a few ADs take it, including an Ezreal who ended up doing 50% of squishy champions' hp with a Q so I think it really got the ball rolling for him. Glacial Augment also looks like a bitch to deal with but the Spellbook seems weak. The Contraptions rune looks kinda weak unless you absolutely need a Stopwatch for Zed. Magical Footwear is hot garbage and i assume Minion Dematerializer is the same unless you start losing the game and kill every super minion rolling down the lane until the inhib comes up (okay you miss 2 supers but close enough). Future's Market is super neat and I'll probably take it on Viktor so you can get Mk 1 at a little more reasonable timing, but I think they should change it to +10/min. Beyond as a rune is pretty solid so I'll give them that.
