Depends what you mean by commercial. There is a lot of scope for commercial heli-ops.
But then when EGSY was a commercial field the prices were higher than most major airports in Europe (I kept my first landing bill there as an example of how to get GA NOT to fly into an airport - you can land 8 times at Gamston for the same price).
So we don't want Easyjet & co there (they can go to Finningley) but a few King Airs, Learjets & etc would be OK. There are two hangers full of them at Gamston but I've heard Sheffield turning them down in the past.
Look at the expansion of Gamston today. 8 hangers full today and two more to be built, plus ground parking. Loads of movements.
Lobbying has to be on commercial grounds - ie the committment to keep the airport open to '07 at least. It was built with public money.
And if the current operators cannot make money from it, hand it over for a £1 to somebody who can.
Now there's a thought ....