System redo help

[Fragmented]

There is a lot of space under the house, and not much under the tank. (I would like to use the under the tank space for a frags.) We are going to expand the tank downward.

I know I will have to get a new pump that will be strong enough to make it up a 12-15 foot return. Is there one in particular I should look into? I still want to stay on the quiet side.

Is there any order that is best to plumb the skimmer (PM Bullet), sump (I guess a 75-100 gallon rubbermaid tub), top off, and fuge?
Are there advantages to having the skimmer in the sump instead of inline?

Does anyone have any words of wisdom?