There's a category hierarchy there. The Deceased category is a top level category that should only contain other categories, such as Natural Death, Accidental Death, Murder Victim and Suicide Victim. There shouldn't be any people directly in the Deceased category, they should be in one of the lower level categories. The people that are there should be moved...
Oh - Just looked at the 3 people that appear in the Deceased category. They all are "unspecified" deaths. So perhaps we need another category within the deceased category "Unspecified Deaths". That woul be the best solution.
That won't be necesary. In the episodes, if a character died in an awfull way or had an unnatral death, they won't miss the chance and say it. If it hasn't been said anything, we just know that someone died, that means that the person had an natural death.
Suspect is a little bit loosely defined. I would consider it to be anyone that had been considered a suspect for the murder (or murders) that are a part of the episode. Doesn't have to be an official suspect, but could be someone who Barnaby and/or his detectives are suspicious of.