Customizable heart rate zones

I appreciate the somewhat recent inclusion of HR zones! However, it could be set up in a much more useful way, specifically, the way Garmin sets theirs up. First, they allow the user to select either percent of absolute HR or percent of heart rate reserve (HRR). Second, and what I’m lobbying for, would be to allow the user to fully customize their zones. For me, Zwift’s default zones are highly bottom-weighted, providing very low sensitivity to efforts at the top end. For example, I’m only able to sustain Z4 for approximately one minute. Customizable zones really should be quite simple to implement. Thanks for the consideration!

Yes, I agree. For me it is the other way around. Majority of my effort is within z4/z5

Please let us customize the zones.
I use Garmin Connect to summarise my training, and Swift give me totally wrong zones and are useless.