I switched to Calendar 366 Plus as my menu bar calendar on Mac and it’s perfect for my needs. The icon shows the date, it supports natural language event creation and understands slash notation to specify the calendar name. It even does a nice job highlighting events in the month calendar when they are selected in the list view.
For only $10 it was a small investment with a big payoff. The CPU and memory footprint are small and it does exactly what I need it to.