The answer to that is to not indict the obvious crimes. The answer to that is to not DO the obvious crimes.
The standard Trumpderps want is one where any Potus candidate can go on a crime spree and never be prosecuted as he just has to say 'I am running in the election', as the 4 year cycle of elections means they will all almost certainly cross one election from the beginning of the investigation, to the day in court, to all the appeals.
No way around that. You either give obvious criminals like Trump a pass or you charge them for their obvious crimes, despite they fact the trial will impact an election cycle.