[3][4] A 2017 report of an expert commission led by Laura McAllister suggested an increase to between 80 and 90 Members, switching to single transferable vote (STV) and enforcing gender quotas.

[2] As part of the 2021 co-operation agreement between Welsh Labour and Plaid Cymru, the parties agreed on an expansion of the Senedd to between 80 and 100 Members and a more proportional voting method, one that integrates gender quotas.

[9][10] Although the Expert Panel preferred the single transferable vote to any other method, the closed list PR system was favoured by the Committee over its capacity to enforce gender quotas through mandatory zipping.

[13] Welsh Conservatives have opposed the Senedd's expansion plan, which they fear would be costly, and have called for a referendum, arguing that only a public mandate can give legitimacy to such a reform.

[16] On 10 May 2022, Conservative MS Darren Millar, resigned from the Committee in disagreement to the Drakeford-Price joint statement, saying "Wales needs more doctors, dentists, nurses and teachers, not more politicians in Cardiff Bay".

[17] On 18 September 2023, the Welsh Government published its plans for electoral reform as part of the proposed Senedd Cymru (Members and Elections) Bill.