Good game and AAR!

As always there are a multitude of opinions on battlefields. The Derwent at Stamford flows over a rock slab and when the river is low it can be crossed on foot, otherwise it averages at around 7m deep. Shortly upstream (a mile or so) is Low Catton, which was once half of a Roman settlement connected by a bridge to the other half in Scoresby. You can make a guess if that bridge was still partly serviceable back then and some folk have suggested that Harold actually launched a two-pronged attack across the two crossing points, with the Northmen making their last stand at High Catton; the only sort of high ground (30m or so) in the local area.
I could see the English approaching from York along the West Bank, trying to fall on the Northmen via a crossing at Low Catton. The famous axeman might indeed have delayed matters, allowing the Northmen to form up hurriedly where High Catton is today, while the English also moved men upstream to cross at Stamford itself, besides eventually succeeding at the Low Catton bridge.
Nobody can be wholly accurate over what was and not was back then, so if having two crossing options gives a better game, nobody can really argue. It's not like Henry of Huntingdon was an eyewitness, he wrote his account some sixty years afterwards.