I've done a lot of construction work, but mostly electrical & framing. HVAC & plumbing a little bit, but never done tile or masonry.
But those two pieces of tile are very large, and I assume very premium.
Using those and the 2 smaller ones where I assume the fixtures are going looks good, and it will save you grout work I assume.
Great job, and being able to do this yourself or with the help of people you know is basically a necessity nowadays.