Two more tips for Ultimate: Your bullets skirt the edge of your Ultimate Range indicator (e.g. it tells you where the middle of the bullets can go, but their large size lets them hit enemies slightly outside it) which catches many people off guard. You can cast W while you still have Ult Vision to land a key root if need be (it may be that you can cancel your R with W for even faster reactions, but I cant say for sure)
Some tips I would give You as a Jhin Main. Talking about Tip Nr. 3 in this clip. To peel yourself even more You can take Fleet Footwork as Your Rune. Dark Harvest is way too situational. And Tip Nr. 5 - talking about the ult. Don't use it to start a fight. Jhin deals much more damage at the start of a fight with his autoattacks and Q. Only use your ult once the last survivors of a teamfight are trying to escape.
Tje ult thing is only true on classic FF/crit builds. His ult slaps even from opening of the fight with DH/lethality-crit. Not as situational as you think. It's more powerful as long as you don't need sustain from fleet.
