What a clever theme - and for online solvers, when the cursor hits 61-Across, the theme answers light up in yellow and blue, which makes kind of a nice abstract art-like design on the grid. It's a bit of a pity that the answers can't show up with their given colors - gray, black, tan, red, and gold - but still, it's a fun idea.
Not a ton of long "bonus" material today. TESTCASE and TEARTAPE are a little dry, but the symmetrical pairing of SENATOR (4D: Long-term legislator) and ENACTED (46D: Passed, as laws) was pretty nice. I also appreciated the pairing of 45A: Cry made while taking a bow (TADA) and 68A: Mythological figure who takes a bow (EROS). They were trying to trick us!
Other entries of note include 54D: Digs made of twigs (NESTS), 35A: Fathers, as foals (SIRES), and 1A: Baker's dozen? (EGGS). Nice! And for 18D: Loony (KOOK), I was thinking adjective but they wanted noun. Gotta keep that mind flexible!
NENA and TREO feel a little old these days, but possibly only because I don't have much else to complain about in the fill. It's not very exciting, but the theme is good enough to carry the puzzle today.