While googling hullness I came across this 2007 public document about Hull's Fruit Market regeneration that credits Urban Kaleidics and Browne Smith Baker Architects. http://www.urbanarea.co.uk/hull%20fruit%20market/Financial%20Modelling%20Paper.pdf
The document includes a "definition" of hullness. We don't want to define it yet as the debate is only just beginning, but this is an interesting point of view:
Hullness - noun1 the fact of quality (of a person) of being from Hull; resemblance of the city (of the place) : The Housemartins show the characteristic of Hullness | there is a real Hullness about the Fruit Market. See notes on Hull- [prefix] and Kingstonian.2 slightly self-deprecating response, in particular to place : it’s their Hullness that criticizes their place before someone else does | there is a real Hullness with this quarter of Rotterdam.3 under-rated and | or underperforming in competitive environments : which of the great Universities did you go to? Oxford, Cambridge or Hull? (Black Adder goes Forth). There is a Hullness about the disappointing final result.4 avoidance of airs and graces : it’s their Hullness that makes them so down to earth.5 opposite of Dullness : Hull is not Dull thus Hullness is not Dullness.6 having a draw-bridge and defensive mentality : Hull is just different to Sheffield and much better than Doncaster in spite of what the current market rates suggest.[ predic. ] (Hull on) having the visible appearance and predictable behaviour of a resident of Hull (occasionally damp footed) : Bob has a real Hull on today because of the rain.DERIVATIVESHull - proper nounKingston upon Hull |Kings:town | up:on hullulll| very propernounORIGIN Old English - hullulluul, of Yorkshire origin.Hull- a prefix city and port in north (subjective geography) of England, situated at the junction of the Hull and Humber rivers; pop. 252,000. Official name Kingston-upon-Hull.