The rune system needs an open mind rework
Conqueror is an issue, make it not do true damage but increase your adaptive stat by stacking when you hit with an attack or a spell
Lethal tempo proc on towers, giving it value to split pushers since very few champions get more benefit from it, even attack speed champions, then from press the attack.
fleet footwork should share it's passive stacks with not only the zeal items, but also dead man's and runic, thus giving it some value to other players, move it to the domination tree
Dark Harvest should proc on abilities
Hail of blades seems more like a secondary rune, though it would be great if combines with like... glacial augment
transcendance with some buffs would make a great keystone
Glacial Augment, transcendence, Hail of Blades, and nimbus cloak are of similar power and value to triumph and presence of mind. Either we buff the other secondary runes (Some are egregiously potent) or we make some secondary runes into keystones.
some of the dirtiest builds in this game aren't reliant at all on the keystone but rather secondary runes.
I propose unlocking the runes with a new keystone in each tree called 'gestalt'
by selecting this keystone, you can chose one other non-keystone rune from any tree, from any tier
if you go domination and resolve you can grab legend alacrity
if you go inspiration and sorcery you can grab cheap shot
and if you go domination with ravenous hunter you can pick ingenious hunter too
all in place of a normal keystone