Any reason why the reduction of the trees was not followed through? Useless management? I think the long incumbent team have already proved they will not invest if there is a cheaper option. Look at the VOR removal for an example. Rather than install a new ILS they were exploring a cheaper GPS based system. Not sure what happened in the end.
They are probably banking on enhances in aircraft opening the door to new opportunities. Let's not forget LCY has routes to Greece and shortly to Iceland. Let's also not forget they have a route to New York. I guess they can probably get away with charging premium prices but so can SOU to a certain extent.
The real hope for investment surely is more and/or bigger stands. Also taxiways to avoid backtracking. These are absolutely musts if they want to open the door to EZY. As other posters have pointed out the starter strip would make little difference. Then again the runway is due a resurface so might be an oprtunity to make it happen.