Then effectively your insert rate is between 16 and 60 per second, sure, you don't really need a sophisticated partitioning or log structured DB. Native static partitioning would give you a decent speedup without much thought.

It's intro computer science, if you have a tree structure and fill it up, you spend a lot of time in the corners of theta notation. Timescale uses tightly integrated partitioning on the time axis to deal with write performance and aging data out. Other popular TSDBs are plays on log structured merge trees etc