Redshift is just a heavily customized Postgres
By tuning the chunk sizes so their data fits in memory, many common queries gain a lot of efficiency. It's built around some assumptions of time-series data: Most inserts and queries are for recent data and are generally ordered.
I've had great experience with TimescaleDB for small-medium time-series loads such as sensor or analytics data; I've found it's pretty plug-and-play and have used it to store tables with ~1B time-series rows of geospatial data, sensor values, etc.