Bunch more driftwood, some big stone either smooth or another texture and some live or fake plants. Google "golden ratio aquascaping" for an idea of "proper" proportions to make it look excellent
Don't be afraid to grab a bunch of driftwood and have it laid across different bits, it looks really natural if its chaotic if that makes sense; if you over think it it might come across too clinical.
Look into anubias plants too, can tie them to driftwood they are super easy maintenance and look great
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