What else should I add?

I upgraded her tank recently and am planning to do another update here soon. I’ve had her for a couple months and had her in a 20 gal while I finished the background. I wanted to get her out of it asap so I only did the back wall of it for now (I will be doing the sides when I’m able to afford the materials again) what else should I add when I do it? Ps. If you can tell from her chunky neck that she’s fat, she was when I got her and I’m slowly getting her to lose weight