Once you move to all Apple bluetooth, things really smooth out. It seems that Apple does way more testing/validating of their Bluetooth stack.
Although of course Apple might well be better anyways; one would hope that billions of dollars in R&D plus caring about quality makes a difference.
Sometimes you have to make a choice on which brands/chipsets you support. Devices on different ends of the compatibility spectrum can basically be mutually exclusive. IIRC if you advertise A2DP some devices supporting only HSP won't work, so you can make some hacky workaround but then your nicer A2DP equipment is harder to use. If you only need to guarantee support for X subset of devices you control, it's easy to tweak the settings so they work well together.