It's arguably an improvement to how it is now. The biggest improvement I think for the whole thing is the enlarged and relocated security area to the ground floor and allowing for more retail space upstairs.
I think the plan LTNman posted above is a good use of the space but it just all looks a little bit crammed in. It's a huge benefit to the airport and a clear increase in capacity, but given the layout, location and relatively small footprint all this will be on, I can't see it being a particularly pleasant airport experience. I would like to be proved wrong.
Another potential problem I see is that a lot of the new stands will be remote stands and it's unfortunate that they can't really do much about that.
Likewise I fear the taxiway system is going to be "inadequate" at the best of times all along the West Apron curve as it looks to remain only a single taxiway (again, can't do much about it). Think of all the aircraft that will be pushing back and blocking the taxiway. Surely the "one way" system they use at peak times will become a more permanent thing even with Taxiway F there.
I wish the airport and everyone involved well for the future, but I can't help but think there is still one or two problems with this development.