While we are looking at Margaret, maybe we can have a look at her parents also. Her profile has no sources and seems to be confusing two sets of Blounts.
In this source (Transactions - Bristol and Gloucestershire Archaeological Society, Volume 17, p285) http://tinyurl.com/guypkkt she is specifically said to be the daughter of Margaret Seymour and that seems to be how she appears in all pedigrees I have seen except the one on wikitree.
According to her will, Margaret left money to Cirencester Abbey for orisons “to pray for the souls of Sir John Hungerford and Lady Margaret his wife, Thomas H. and Christiana his wife, Edmund Blount and Margaret his wife, with all the souls of their consanguinity.” http://tinyurl.com/jyy9pqs
This would suggest that Margaret’s parents were Edmund* Blount of Mangotsfield and his wife Margaret Seymour. The History of the Parish of Bitton says “The next owner of the estates [in Bitton after John Blount who died 1444] was Edmund Blount, his son who married Margaret, a daughter of Sir John Seymour (their arms impaled were on the old church porch at Mangotsfield).” They had a son named Sir Simon, and a daughter Margaret is mentioned in one of the visitations of Essex (can't put my finger on it at the moment.)
Also, this would be consistent with the statement in History of Parliament that Sir John’s wife had “Seymour blood in her veins.” http://tinyurl.com/zjfoemt
*sometimes his name is transcribed as Edward, but he was transcribed as Edmund in his ipm 1468, see History of the Parish of Bitton, p 300: “Edmundus Blount armiger…Edmundum et Margaretam uxorem ejus” He had several Edmunds in his ancestry, and as Margaret’s will also calls him Edmund it seems the better fit
At any rate, I don’t see any support for a Hall. I can't find anything on the Mangotsfield/Bitton side. The only Ellen Hall I have seen marrying a Blount is Ellen Hall, daughter of John Hall of Dovebridge who married John Blount of Burton-on-Trent in Staffordshire. Perhaps they have been confused somehow?