The hygro would like some fertilizer, it should grow pretty fast. It looks maybe a little pale. The anubias doesn't really care, they just grow slowly. You can use liquid ferts but if the hygro has good roots you can try roots tabs instead. Your gravel may damage roots as you replant the pretty tops, it's quite coarse. Be gentle when you do, try to make a trough with your finger. Then while holding the end between thumb & middle finger backfill with your index finger. It takes some practice, but with hygro you'll get lots of that, lol. When it gets too long or bottom leaves die leaving a naked stem you can just pinch off the good top & replant. & either leave the "stump" if it looks good (it'll branch where you cut) or if ugly just remove it. I have fingernails so I can use my thumb to pinch but you can use scissors. Anubias leaf stems are way too tough so snip any damaged, yellowing or algae infected older leaves if needed, old leaves never just fall off IME.
What is the dwarf hairgrass or lilaeopsis (sometimes still called dwarf chain swords) looking plants by the hygro? I've never had good luck with hairgrass because it would like co2 injected. But I have had dwarf swords with root tabs in low tech tanks. Watch out that it doesn't get shaded by the hygro.
If you want some other shape/color plants, cryptocorynes are easy & come in several sizes. Wendtii crypts come in several colors like red (ish) & Mi oya (maroon), are fairly small (4-6 inches) & easy to find. They'd like a root tab nearby & the crown just barely above the substrate.
8 hours is just a bit long for low tech lights to be on, you might try 6 or 7. I have no opinion on LEDs, I don't use them, yet.
The filter return height above the water surface isn't too important to me unless it's too noisy to hear the phone or tv, but it will speed up evaporation. & no, topping up tanks doesn't count as changing water, lol.
