Is it bad form for you, a frame builder (I am not) to basically copy a bike's geometry?

Let's say I really like the geometry of the Surly Long Haul Trucker but I want it in Reynolds 631 or 853. Would that be an issue for a builder?

Second question. Hoping you are familiar with this bike above. How would lowering the top tube on the seat tube (so that it is slanted down) effect the bike? (Keeping the rest of the bike exactly the same. How would this change the ride?

In case you are not familiar...