I would second “Hector the Hero” for a slow air: originally in A but a lot of people play it in D to accommodate any whistle players. But if played in A, you can play it on fiddle first in the lower register and repeat an octave up.

For another slow beautiful air, avoiding Ashokan, Da Slockit Light by Tom Anderson.

A couple of nice English jigs:
The Oyster Girl and
Seven Stars (aka the Moon and Seven Stars)

Some Waltzes:
Margaret’s Waltz by Pat Shuldham Shaw
Midnight on the Water (another vote) Luke Thomason
My Cape Breton Home by Jerry Holland

A couple of Shetland reels:
Lay Dee at Dee and
Da Ferrie

Some easy polkas:
Eagan’s
Rattling Bog
John Ryan’s

Ok, that’s 12, not 10.
Ask me tomorrow and I’d probably choose a different selection!