I'm designing and building a sitting bench out of yellow cedar (Alaskan Yellow Cedar, Nootka Cypress, Cupressus nootkatensis). This will be used outdoors so I'm debating design choices while considering wood movement. Top dimension is 14" x 44". Legs are inset 6" from the ends and 1" from the faces.

The wood is quarter sawn and 2.25" thick. The top is three pieces. The legs will be joined directly to the top with double wedged through-tenons. I've cut the mortises and tenons and dry fit them. I have not joined the three top pieces together yet, just clamped everything together for now. The legs are joined in the outer two top pieces with another piece in between.

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The inside distance between the tenons is a little over 7". Using an online calculator, I estimate potential wood expansion and contraction of the top at 1/16" between the tenons (going from current 8% moisture content to 15%).

Question: Can I get away with edge gluing (and likely throwing in some 14mm dominos double pegged from underneath for piece of mind) the top into a solid piece AND putting stretchers between the legs front to back?

Options I'm considering:
a. Edge gluing top and adding stretchers between the legs near the bottom of the legs.
b. Edge gluing top with no stretchers between the legs (which eliminates any wood movement problems but sacrifices strength)
c. Splitting the top into two pieces with a curved cut down the middle and adding stretchers between the legs top and near the bottom. Also, adding a slotted screw up through the top stretchers into the top near the center cut.

I hope that's clear. I might be overthinking this!

Appreciate any thoughts on this.