What's a good milestone after 1500?


You could always try going by ranking. For example, aiming to get into the top 20,000 in your country or top 100,000 in the world or 99th percentile etc. There are always so many players at the same rating as us which makes it easy to dismiss our achievements, so something more concrete to be proud of might work well for you. Imagine being able to say to yourself that you're in the top 1% of online blitz players.
So this summer I decided I was gonna try to get 1500 blitz, and im like 20 elo away from it right now, so what milestone should I try to hit next?