Aquariums: My first tank is coming along! Trying to figure out what fish to get

Hello all! I just got into the hobby 3 months ago with my first aquarium and absolutely love it. I currently have 15 cherry shrimp, 1 amano shrimp (saved them from my evil Betta's tank), and 6 very fat otos. I'm really stuck on what to get – I'd love something that swims in the middle of the tank, colorful, peaceful, and small but am open to any suggestions 🙂 thank you!