Face is too open!
nope - that is what is comfortable for that batsman - how open the bat is on take back is largely irrelevant.
I really don't know much about wicket keeping (or tennis - but I understand the "quick-step" idea) - but the trigger for a batsman doesn't have to be a foot movement, it can be part of the pickup of the bat or a flex of the knees - so while you say 99% of batsmen have a trigger, it isn't always a foot movement. As I have said once or twice - most amateur batsmen move around far too much and by staying stiller they find it much easier to pick up the length and line of the delivery.
if you do go down the foot movement trigger route you need to have it coached into you and as this is done wrong so often I actively discourage it - you have to understand about your starting position, when you trigger, where the trigger in the crease takes you. As well as doing it whilst keeping your head still and eyes level.
Why bring all that complication in?
In golf you can use a forward press, again it is only a "fidget"