Vallisneria

Best beginner plants imo -> hornwort, crypts, frogbit, any moss, pothos (dont even have to plant), amazon sword, and vallisneria.

Tall grass-like background plants that are beginner friendly sounds like Vallisneria.

For the plants, I would pick Vallisneria. It's a seagrass-like plant that will sway in the current really nicely. It's easy to grow, you can grow it in gravel with root tabs fertilizer.

Limnophila Sessiflora and vallisneria are two super low maintenance plants that will grow nicely even with a stock light.

Vallisneria is a great family of plants to look out for to fill tall space and grows in basically any substrate and basic light.

I have excellent luck with Vallisneria, Cabomba, and tiger lotus.

Background: Vallisneria, Amazon Sword, and Sagittaria.

Salvinia minima, hornwort, any kind of anubias (specially nana), vallisneria, guppy grass and Java moss

I have Amazon Swords, Java Ferns, Vallisneria, Anubias Barteri, and Water Wisteria. Dose with nutrients once a week, root tabs once a month or so, low light, and they do great.