this is not (really) synthwave... :)
anyways, good try! i'd add more and make it sound less uhh... loopy?
TIP 1: If you use samples, you should at least add a few effects to add more variation: a few filters or a flanger on the guitar for example. And you can enhance the mix even further by perhaps adding a baseline with a pulv.
TIP 2: If you use samples, try to use the ones that are uploaded by other artist (the ones with an orange dot in front)
