While my preferred option for House of Lords Reform would be to simply restore the pre-1999 status quo, we have to admit that even then the Upper House was not perfect, though not because of the hereditary peers.
If we have to move forwards, my idea would be as follows:
Create a hybrid model designed to satisfy the need for the “dignified” the “expert” and the “democratic”.
The bulk of peers under this model would consist as follows:
1/3 hereditary peers selected as now from among the pool of hereditary peers but with a minimum age requirement of 35. This retains the “dignified” part of the constitution. After all; is it really the House of Lords without the hereditary peers?
1/3 appointed peers selected by an appointments board with nominations from the general public as well as politicians - again, minimum age of 35.
We could also deliberately build a few “rotten boroughs” into this appointments system with certain ancient universities and other organisations (like the Royal Society perhaps) having an automatic seat which they can fill in whatever manner they decide.
Finally, 1/3 would be decided democratically by regional PR. Each region should roughly mirror an ancient kingdom/region of the United Kingdom (Mercia, Wessex, Strathclyde etc) to provide some historical basis and each of the regions would have an equal number of peers regardless of population.
This would give power to geography and prevent metropolitan dominance. Under this system London would not become its own region. The different parts of the capital would simply fall into whichever geographical region they are in. Again, there would be a minimum age requirement of 35.
This final part of the system would hopefully scratch the PR itch but without jeopardising the FPTP system of the Commons. It would inject different viewpoints into Parliament and occasionally shake up the political order in the Commons itself as MPs adjust to take account of insurgent opinions and causes.
We should retain the Bishops and restore the Law Lords.