I want to make two or three points:
(1) There is no one theory of the good or version of the good life that fits all.
(2) There may be some values that I and/or most secularists stress - kindness, sympathy, reason and science, creativity, individual freedom, tolerance of difference.
(3) But the essential thing is the need for us all, from within our comprehensive views of the world, to abjure the use of state power to impose our contestable views of the good on others. We should stick with persuasion. Secularists should take this view (though they don't always) and so should religious people (though they often do not). This would include freedom of religion but also much more, such as free speech and the Millian harm principle. Reasonable religious people should sign on to a framework of secular political principles such as these. If they don't, they will be regarded as unreasonable by liberal secularists and will have to take the consequences of that.