Start-stop clock won't work unless you do it for every time the ball is dead - teams that want to delay the game, break momentum up, or recover will just agonise over free kicks, throw-ins, goal kicks, etc.

Stopping that from happening would require refs to intervene to force them to play - they already don't/won't enforce the current timewasting laws at their disposal, why would this suddenly change?

Just adding all the added time on was a good system and discouraged time-wasting.

Also the claim that the Prem has actually tried to crack down on time-wasting within the current is frankly laughable. At best they try a new approach for a few weeks, crumble when it gets criticised in public, and we never see it again.