Finally upgrading aquarium, what options can I add to aquarium? live plants?

Ive had a Betta now for about 9 months and finally am moving up to a good sized 20 gallon aquarium. Wife approved woo!

Anyhow, have it setup and water in getting acclimated for the week.

So, it's been a while since I have been in this sub and looked around. I am kinda wanting to add something to the tank other than the typical rocks and fake plants.

What is everyone adding to their tanks? what is it all called? Anything I need to know getting into any of it?