Okay, there are a lot of nano fishes that you can consider...
Mostly are eviota and trimma goby... Yasha and yellow nose goby is a good choice... Blue-stripe pipefish is also worth a try when your tank is more mature and stable... You can also try keeping neon goby, both yellow and blue... Red-head goby is a very good choice, a small fish with a lot pf personality... For goby one on the rare side, can try gressingeri goby... Worm goby is also a good choice but rarely imported, haven seen one for some time liao... Hectori and rainfordi goby is a very good choice also..
For shrimps, you can try looking for red spotted shrimp, yellow arrow shrimp, emperor shrimp, anemone shrimp and sexy shrimps... They stay small and is ideal for nano tank...