How can I improve my starter bow set?

Received a Diamond Edge 320 as a gift last year and have been target shooting more and more with the weather warming up. I think the sight is just okay, and with the whisker biscuit, honestly just unsure if there's something better out there? To make the next steps towards an intermediate shooter, what do you recommend replacing?

I think I'd prefer a single pin (or double) vs. the multi-pin setup I currently have but I've also never shot one so idk. Also wondering fixed vs. adjustable, which is better? Currently just a target shooter, but open to hunting down the road. Budget is up to $400