" Is there a strong preference on Anderson 400 versus Jeld Weln Site Line? "

There is nothing in the way of quality with anything Jeldwen in my opinion. Being the choices presented, 400 Series by Andersen. But were it my druthers I would look at Marvin Elevate or Essentials as I am not really a 400 series fan.

To get good advice regarding appearances you need to show us what the house looks like.

Elevate with the split finish. Probably the best bang for the buck too.

Do they have wind protection?

We are getting a quote on Marvin Elevate.. We did like the Anderson doors multi locking system

Marvin should have about the same system.

Will look at Marvin doors for sure!! We did change roof line on porch and changed windows on the tower..

Nice house but I'm curious about the twin stairs.

We have gate under house to get to elevator for disabled visitors and family..

Coastal South Carolina requires impact windows, is that correct? Just confirming that is what you are looking at.

Marvin has Coastline casement windows for coastal conditions. Coastline Casement Windows | Marvin Large glass sizes are possible. You may be able to increase the view with fewer windows in larger sizes. Consider using fixed windows for as many as possible. Your drawings show double hung. It'll look more modern and current with unobstructed casements in larger sizes, imo.

Stay away from Marvin products and warranty are crap.