We have spent quite a bit of time investigating how validation improvements might be achieved, whether that be through validation as a background task or whether it be with improvements on the speed of validation in the first place.
There is no silver bullet which has been identified so far, the validation is already very efficient with minimal potential for speed improvements and there are issues with it as a background task as previously mentioned which we haven't got fully fledged solutions to yet.
Thanks for the great idea, there have been multiple improvements to the validation performance over the past few years to overcome this. If you are still experiencing issues please feel free to let us know but at this stage we will not be implementing this idea.