Would civil union not be a better way out of the inheritance issues ...(and elsewhere) suggesting marriage and civil rights give more rights is wordplay

In a way, yes, but it would need a much bigger shift of attitude than we have seen so far. There are a lot of people whose choose not to marry because of its historical associations or because of the huge costs that weddings now incur. In many cases the couple do not consider the inheritance implications of that. So I would like to see a civil union for anybody - gay, straight, siblings who share houses, good friends with a flat in common and so on - that is entirely about taxation and inheritance arrangements and could be altered several times a year if appropriate with no massive costs and be sufficiently mundane that it never reaches the level of a social event. Simultaneously, I would like to see a marriage that is much more permanent social arrangement and broadly what we regard, socially speaking, as a marriage now. And we can keep all that separate from the hoo-hah of a wedding as well.