On the Pope v Bairstow, think it's important to look at when and where Bairstow has his runs. In recent years he has been abysmal against pace. Pope has been terrible against decent spin. Neither has been very convincing so I'd look to get Lawrence in, if only because he's shown a bit more spine than either this year.
Ideal world, Buttler bats 6 and Foakes keeps but they've sent him home. Lawrence has an excellent record for the Lions in Aus and personally I really rate him.
I would also pick Lawrence, the reason being because you know what you are getting with Pope and Bairstow and it ain't pretty, I think it's quite obvious Lyon is all over Pope and the Aussie quicks will be targeting bringing one back into Bairstow to get him bowled like he has been.
So with Lawrence there is a sort of lack of history there, a chance for him to make a mark etc....
But TBH have can't see them making any changes, after what Root said. Burns batted better 2nd innings, obviously Buttler saved himself and they have flown Foakes home for some ridiculous reason. They like Pope otherwise they wouldn't have picked him in the 1st place, and they won't want to admit they were wrong after 2 tests.
Only changes will be to the bowlers and who knows what they will be considering the 1st 2 tests!