System settings-->my device-->language and input--> click cog wheel to right of where it says Google keyboard--> click Vibrate on keypress. It should be right there.
If you don't see Google keyboard, click Default first and select Google keyboard then continue with the instructions.
On keyboard options, go to advanced settings, Turn the vibration time to 60ms+. That is when it is basically on par with stock keyboard. I have mine set to 100 because I prefer more feedback. I am still looking to find a way to change the time for the shortcut keys to increase that response along with vibration when you open apps/swipe pages.