I understand that new stuff aren't truly tested until they've been to production. Same goes for champions and Riot's release cycle. This is problematic because it can be abused for Freelo.

Here's why:

Rakan: high mobility, easy Alistar combo, Multi Charm CC

Xayah: stacking damage mechanic, untargetable ult, AOE Snare, feathers provide zone control

From the mirror lane matchups I've played, it's almost always better to start with Deadly Plummage as it gives Rakan the ability to trade. Rakan should either start with shield or the knockup. The Heal poke is not really a poke, it's nice to use right after a knockup.

Buff/Nerf suggestions

Xayah: Decrease attack speed on Deadly Plummage, Increase feather expiry time

Rakan: Increase cooldown on knockup, Increase healing, increase shielding range for other champions