Each Anglican is left to his own conscience here. We won't get a consensus. I think they're pointless. Obviously Christians celebrated the Eucharist on tombs of martyrs, and most early churches were built over them, but those are circumstances arising from persecution, not infallible decree or necessity. Our acceptable worship is faith, contrition, confession, loving others, doing the works of Him that sent us, and a turn of our whole existence God-ward as one comprehensive sacrifice. Do Anglo-Catholics follow the Roman practice of placing a relic in their altars? I've often wondered about that, since the Orthodox don't do it.
I can understand how seeing something from another tiem and place, connected to someone from history you admire, or an important event is awe inspiring. I have a lways been fascinated with early British antarctic exploration and I have a key ring made from a piece of the original ship planking that Scott and his crew walked on during the 1910 expedition. To think those people seperated by a hundred years we can have soemthign in common sets my imagination on fire. In Ednburgh there are lots of places cnnected with the Reformation. In St Giles you can see the very pulpit John Knox preached in and his house he lived and died in. In St Andrews there are marked spots where the first protestant martyrs died - George Wishart and Patrick Hamilton can still be seen, as well as traces of burnt soot on the buildings. To place your hands on an object that Knox or Scott would have touched, and to look across buiklings and places they would have seen...it's the nearest thing to a time machine, a reminder these people and places were real. I feel differntly about body parts. I feel thes are human remains awaiting the day of ressurection. They shoudl be buried, to cut them up, divide them and put them on show seems to me to be deeply insesitive, to the living family, and to that person who I doubt would want it most times. To house them and other objects in churches as objects of veneration also I feel detracts from God's glory.
Some altar tombs have survived the Reformation. A well known one in my Diocese is the altar tomb of St Endelienta, at St Endellion in North Cornwall. (Endelienta is one of our many Celtic saints of the late 5th/early 6th century. She he is believed to have been a daughter of King Brychan of Wales). It's used as a side altar in the south aisle. I can think of one extreme Anglo-Catholic priest in my Diocese who enclosed relics of St Rose of Lima in the high altar of the church at St Hilary in west Cornwall in the first half of the 20th century. The church interior was desecrated by a band of Kensitites who arrived en masse with crowbars and hammers. It caused quite a stir with the RC community who were aghast at the thought of the desecration of the relics. Ironically, the relics went into the safekeeping of the Evangelical Anglican Bishop of the time and the aggrieved Anglican parishioner who set off the trail off destruction died in a RC hospital being nursed by nuns!