The House of Lords has become too big as a result of each successive Government appointing further peers to change the balance of voting power in the Lords. We don't need an second elected house as that will question the supremacy of the Commons to set the direction and policy of the Houses of Parliament.
The Lords does serve a very good purpose in recent times, in its detailed examination of legislation passing thru Parliament, which used to be part of the Committee stage in the Commons. Using it's massive store of experience and knowledge of many of its members to refine often quite crude bills passed from the Commons.
What we need is a smaller House of Lords with a neutral balanced political direction/agenda with the time and expertise to examine in detail proposed legislation and refine it.