Display labels in the email list
Feature
I like to use my Inbox as a "to-do list" of sorts. Mails there are mails that I haven't dealt with yet, either because it's not due time (for example a bill that has to be paid just at the end of the month), or simply because I haven't had the time. To make sense of everything in there, I like to add labels to them in Gmail, e.g. "Bills", "Shopping", "Work", "Personal", etc. When I deal with them, I archive and they show up in the corresponding folder later.
Mail currently supports this well. My only gripe with it is that I'm not able to quickly see the labels on each of these emails.
Check the Gmail web UI:

Just by taking a quick glance at the inbox, I already know what the emails are about. Other providers support this too, like Fastmail and Outlook (I think)
Describe the solution you'd like I'd like Mail to be able to display the labels in the inbox list of emails. They may not be necessary in other folders.
I think all the information needed is already present in the app, since label "folders" are already supported. I'm not sure about the label colors, though, But this feature would be useful enough without color-coding them.
So I think most of the work would be figuring out the design instead of implementing it.