The Welsh Parliament (currently National Assembly for Wales) / Senedd Cymru (currently Cynulliad Cenedlaethol Cymru) currently has law-making powers covering the areas of devolved responsibility what are the arguments for and against a bicameral legislature in the context of Wales?
Currently the Assembly is a unicameral legislature consisting of the elected Assembly Members (AMs), Scotland and Northern Ireland also maintain unicameral legislatures whilst the United Kingdom as a whole has a lopsided bicameral legislature.
I'm aware that this question could be boiled down to a simple "is a bicameral legislature better than a unicameral legislature" question. I'm particularly interested in answers which can speak to UK/Europe specific arguments.
To narrow the scope further this question should be interpreted to refer to a second chamber which is roughly equivalent to either the first chamber (current Assembly or House of Commons) OR the current UK House of Lords. I.e a second chamber which is entirely equivalent to the first or a second chamber which exists to 'temper' the first but without the power to overrule or deadlock it.