The milled polycarbonate lids from sources like Toplids really don’t take away much in looks on rimless tanks.The ONLY semi-good reason to not have a screen top is if you run a trimless tank (really does ruin the aesthetic). I don’t use a top on my frag tank - none of them have jumped yet. At the risk of being provocative, it’s idiotic to not have a screen top with a standard trimmed tank. You will lose fish, guaranteed. If you have a cat, or perhaps a dog, they’ll clean up the evidence leaving you to wonder what happened to Freddie the fish. Screens are dead easy to make, and dirt cheap. I near my fish hitting the screen all the time. Occasionally hard enough to actually dislodge them.
The only time in the last 20 years that I did not use a screen was when the light canopy sat directly on the top trim. Sides effectively re-route any jumpers.