Please help with measurements for my master bath. Builders wants me to make a mock up of how everything should be installed and is working on plumbing and electric now.

*vanity is 36" x 8.5' with a 3cm countertop, ceiling is 10'

*undermount sinks: https://www.homedepot.com/p/KOHLER-Yepsen-Glass-Undermount-Bathroom-Sink-in-Translucent-Dusk-28823-TG1/324697391

*wall mounted faucets: https://www.build.com/brizo-t65776lf-lhp-eco/s1689383?uid=3989190

*I have 2 2x3 mirrors that I want to frame with moulding

Questions:

*How high should the faucet be mounted? How high should the backsplash be?

*Is the faucet going to look funny with only one handle? I didn't think of this before, but I'm worried it will throw off the symmetry.

*With a 3cm backsplash, will the faucet reach be compatible with the sink?

*How high above the backsplash should the mirror be? I'm thinking vertical since the ceilings are high. This is the light that will be over the mirror https://www.homedepot.com/p/VAXCEL-Elsa-28-in-W-4-Light-Satin-Nickel-Capiz-Shell-Coastal-Bathroom-Vanity-Light-Fixture-W0271/322852963#overlay

Thank you so so much, and if anyone has mad skills and can mock it up, even better! Otherwise, I will try to draw it out. I'm kinda flying by the seat of my pants here!

Here is the bathroom layout and vanity plan (except cabinet will be up against the left wall, as in the plan

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