Churchyards are very special places. Their ambience comes from the memorials, the church itself, and from the history of the community that the place encapsulates. Memorial design is controlled to ensure that those special qualities are retained and enhanced when new additions are made. Follow this link for guidance.https://www.churchofengland.org/sites/default/files/2018-11/CCB_Memorials-in-churchyards_Sep-2016.pdf
