Looking for advice/best practice: I have 'Lost' as a stage in Deals. Right now, Lost's 'Forecast Category' is 'Omitted.' Should it be changed to 'Closed.'?

Also, I have a category for imported Deals (were events in old system) that I feel is making my reporting all wonky because it's still in the 'Open' Forecast Type. I'd like Deals in this stage to remain but just be outside my regular reporting. Is there a way to do that? They're not necessarily Closed Won OR Lost.