You can still name your releases if you use Semver. You can for example call it 1.2.3 John, 2.0.1 John, Then if the next release is really big you can name it 2

You can still name your releases if you use Semver. You can for example call it 1.2.3 John, 2.0.1 John, Then if the next release is really big you can name it 2.1.0 Phil. Then when talking to customers you can ask them if they have a John Or Phil version.