Everything we know about exercise suggests that you should be achieving a very high, nearly optimum level of overall health benefit with this regimen, assuming that you do push into higher heart rate zones for spurts of varying intensity and length on most rides. The idea that you can either do 'what you're doing' or something 'optimally healthy' is a false dichotomy.
Now, if you're somehow staying at strictly 70 percent of max heart rate and making sure to never vary then, sure, this could be improved but riding a bike usually just isn't like that.
Last edited by Flipper_; 07-26-22 at 02:14 PM.