I am new to Houzz and in the midst of a master bathroom remodeling project. My dilemma is what size to use for mirrors. The layout is that there are dual vanities (same size of 40" Ht x 77" Width) with a closet door in-between them. There is one sink in each vanity that is centered within the vanity.

The Old bathroom sizing:

-Cabinets 40" Ht x 77" Width

-Mirrors 55" Ht x 77" Width

-Soffits 25" Ht x 77" Width

-Canned lights in the soffits

-Ceilings 10" (but included the soffits)

Mirrors were edge to edge from the wall to the closet door on both sides.

The New bathroom sizing:

-Cabinets 40" Ht x 77" Width (using same cabinets)

-Soffits are now gone so I regain those 25" Ht.

-Purchasing a 4 bulb vanity wall light that will be above the mirror - above the mirror and vanity. The unit is 10" Ht by 36" Width

-Ceilings are 10' (120").

If I take into account the cabinets of 40", with those ceilings of 120", I have 80" in Ht still to use. That mirror size for both Ht and Width do you think I should use. I think that I should have a few inches minimum on all 4 edges. Should it be more? Should I allow more space on top with the lights? Are there any specific measurements or percentages of a wall that I should use to figure it out?

Help please!!

Nicole