what do i max as cho

W, easy to land poke+wave clear, and most important longer silenceduration

Ryze is a champion that needs to spam his abilities to do damage, hence why his cooldowns lower when he casts an ability, so for Cho, your best option is to max your W for the silence. This prevents him from doing anything since he can't cast anything for the duration.

Against Ryze (and most ranged champions), I would recommend maxing Feral Scream. It increases the slience duration, gives you some waveclear, and ranged poke.

Against melee champions, I would recommend maxing Vorpal Spikes for the waveclear and increased autoattack damage. That allows you to save mana when trading and to save your Q and W for their CC instead of damage.