Ideas for a minor Xerath rework!

As most of you may know, Xerath as a champion is fairly...lackluster? He's not weak by any means, but he doesn't seem up to par with a lot of the other mid laners. His scalings are good, but his overall damage output lacks against other mages with more reliable abilities such as Ahri, Veigar, Cassiopeia, or even Lux. His passive, though being fairly useful in laning phase, doesn't do much of anything in the middle or lategame. His primary weaknesses in terms of damage are that he has trouble even landing his spells in the first place. This is why I'm proposing a change to his passive which would help alleviate a lot of the problems Xerath suffers from as a mage, yet help him shine later on whilst retaining a few of his core weaknesses, such as his issues with dealing with assassins. These numbers may be a tad high, since I'm a tad tired and wrote these in about fifteen minutes, but you can understand the basic gist of what I'm seeking to get at here! Please give me feedback, as this is a bit of a "first draft" of an idea I had. So the numbers may be a tad off.

Passive: Arcane Ascendance

Each of Xerath's abilities gain upgrades with each rank you put into them.

Q - Arcanopulse: Each rank put into his Q, he receives minus 0.2 seconds on the time required to charge it to its max range. At rank 5, Arcanopulse's hitbox comes out 0.2 seconds faster upon release of the spell.

W - Eye of Destruction: At ranks 2 and 4 of this ability, the time which it takes for the spell to land will be reduced by 0.1 seconds. At rank 3, the ability's maximum slow takes effect throughout the entire hitbox, rather than just the middle. At rank 5, he gains a bonus 0.05 seconds off of the hitbox landing, and the damage in the middle of the spell is amplified to 65% bonus damage, rather than just 50.

E - Shocking Orb: Each rank into this ability following the first will increase the speed at which the ability travels towards its target, as well as increasing the length of the minimum stun at melee range by 0.1 sec per rank. At rank 5, striking an enemy with the spell will mark the target, causing his next spell to deal 10% bonus damage to the target.

R - Rite of the Arcane: Rank 2 of this ability will reduce the static cooldown between casts by 0.2 seconds. Rank 3 of this ability will reduce the static cooldown between casts by another 0.2 seconds and his Arcane Barrage will land 0.2 seconds faster. When Xerath kills an enemy with his ultimate, he gains one extra Arcane Barrage for each champion killed, as well as a refreshed duration of how long he may stay within the immobile state of casting his ultimate.

Other minor kit tweaks I'd go for would likely be as follows:

-Grant Xerath's W a minimum range of around 400 - 450, similar to Cassiopeia's Miasma. This way he still retains his lack of ability to peel assassins off of him.

-Up the AP scalings on his Q by around 5% - 10%, yet decrease the width, as well as causing it to only deal full damage for the "first" (closest) target hit. This way he still retains moderate counterplay in the lategame, even if his early game suffers a bit.

Thank you for reading this far! If you find these changes interesting, feel free to support my ideas! I'd be positively filled with Joy if a rioter were to see this post and grant me some feedback as well. Thank you! [slayer-jinx-catface]