Solid colours for Calendar and Agenda sidebar

Upgraded to version 5, everything seems fine except I’m in the category of people who takes awhile getting used to new user interfaces. After one week of use trying really hard to absorb the new look, I’m not convinced.

One thing in particular is very annoying. The calendar colour scheme has gone from good to worse in my opinion, now being very translucent with no option for solid colours. Also the Agenda sidebar which in my case list items from 6 different calendars, now has incredible faint colours which makes it hard to tell the difference. At least in version 4 you could distinguish different colours, not anymore. PLEASE bring back the option for solid colours in Calendar and Agenda sidebar.

Can you please make a screenshot? Actual colors depends on selected theme, OS and other things.