PvZ - I need some timings - Platinum

When I face Zerg nowadays, this is what I tend to do:

I open Nexus, Cyber, Stargate into Oracle harass, then produce 2-3 oracles and use them for scouting and map control.
I go for ground upgrades, storm and a mix of zealots, templars with storm, sentries and archons as my main force. 
I send Zealot run-by's and Warp Prisms to harass the zerg's 3rd, focusing on bringing down the hatchery. 
I force any early engagements on ramps, choke points and if I do attack, I make sure to use zealots to strike in 2-3 different locations at the same time.

My questions and where I seem to struggle:

  • How many gates should I have and by what time? (I always seem to have too little Warp Gates)
  • When should 1-1, 2-2, 3-3 be completed? When should Storm be completed? 
  • When do I take my third?
  • When should I be maxed out on my army?

Usually, the game ends by this stage. However, if it lasts longer, what tech switch options do I have? What can Zerg do, what are my options to react?