I'm no pilot - just humble SLF with some very peripheral involvement with aviation. I do know something about the law however and I humbly submit that the offence within the UK is fully covered by Article 222 of the Air Navigation Order, 2009, which states that it is an offence to "direct or shine any light at any aircraft in flight so as to dazzle or distract the pilot of the aircraft". It was enacted I believe specifically to tackle the growing menace of laser attacks on aircraft. A similar law has recently been enacted in the U.S.A. to make it a federal offence to commit such an act.
So, the problem isn't so much the lack of legal muscle, as magistrates and judges simply not taking the offence sufficiently seriously when sentencing. I would fully support any petition or other action, however I think the appropriate target in the UK should be the Home Office with the objective of encouraging clearer guidelines and stricter sentencing to the Courts.