Kai'sa top is actually good.
I mostly run barrier because it helps me so much surviving some bursty bruiser and combines so well with PD and my R. Ignite i don't really need as they can't really outrun my E speed and botrk slow.
I don't really aim to upgrade the skills as i prefer some items situational top items first to be able to duel almost anyone.
So botrk is pretty decent against almost anything on top so i just try to rush it and survive lane till i complete it. Then i usually manage to build 40-60 cs lead with hard bullying and freezing and 2-3 kills. Then i go for PD and TF to be able to evolve e and for the q i need additional pickaxe that usually builds into IE as 5 or 6 item
So why did i decide to go Kai'sa top?
Most ppl bring lucian and vayne top but i thought kai'sa might be just as viable if not better.
It's kinda dumb but as an adc main i got really annoyed by the supports in my elo and that bot lane is dependant on the 2 of us and not just me so i said fk it and started queing up as top / mid.
So i decided to try my primary adc as a solo laner and it kinda suprised me.
So far i managed to force an aatrox and shen to swap to mid lane because of how obnoxious it is to play against my E and R + all the mixed damage. and beat up a jax pretty darn hard. Late game wasn't much of an issue as i can dodge his counter strike prety easily with E or R.
Won 5/5 with it so far will see how it goes against the other supposed counterpicks. But it looks really promising being able to dumpster Jax, Shen & Aatrox.
I suggest you trying it out, cheers :)