Autohide Home Indicator (bottom) and Three Dots (top) will be added in the next minor update. The problem is tapping near screen edge makes Three Dots reappear, so we cannot make top toolbar smaller.
To remove Three Dots we would have to disable "Split View" support. Unfortunately it must be "hard coded", so it is not possible to make a switch for that in Preferences. So we cannot do it.
Besides Apple removed "Allow Multiple Apps" (split view support) option from iOS Settings.