Hi
I don't know if one, two or more releases each year is good. As user is without interest.
The more important is to have an easier update. Actually I know only two projects very nice to update : dolibarr and piwik.
As developper, other aspects, I don't try anymore to use plugin, because is often broken or without maintenance. Also I don't try to propose PR or patch, between two releases I'm sure to lost these changes. Actually it's easier to maintain locals patchs and run a routine after each update.
And dolibarr communication is poor, for example, release notification are often forget in this list.