Pass a bill that requires the (non delegated) permission of the Attorney General to bring a prosecution under any law or regulation which has not seen a successful prosecution within say the last 15 years.
This would save repealing old rubbish, the police / CPS would know how unlikely a prosecution was and so would only use these old laws if there was no other choice and by not delegating the power the number of frivolous requests would be kept down
Why is this idea important?
It saves trawling through all the old laws one by one and having to repeal them individually.
It means people can concentrate on those laws that are actually enforced – for example why issue police with thousands of pages of guidance – focus them on the things that actually matter.