But the runway length >3km should be more than enough for any type aircraft (even A380) to land on. I think it will be more of an environmental issue, as well as creating the infrastructure for the additional flow of people to and from London and surrounding areas, that will block this idea from becoming realised.
Schiphol is having the same sort of debate, reaching the limits for sound pollution every year for the last 10 years. The latest plan - and the one most likely to be carried out - is to expand Lelystad airport (EHLE), which is the most logical choice, as it is already owned by Schiphol Group. It also it my home base for GA flying, so I'll just have to see if that remains affordable as land prices sky-rocket, and ATC fees are introduced... MLA and VLA operators are already being bullied away by closing down the little grass runway (A terminal building will be built there, and/or the needed parking space). GA operators are asked to present relocation plans
