0-1= minor league closer not the best option.
1-3= Below average closer, probably set up man
3-5= League average closer. 30-35 saves
5-8= above average closer 40-45 saves a year AS
8-= Top closer solid K rate, walk rate, and ERA 50+ saves All Star
This is pretty basic I will probably post examples later but what do you think.
I honestly hate using war for closers. I think its pretty pointless.
Not only that, but many set up men are more valuable than closers.
According to your scale, jim johnson was a well below average closer this past season. Hell, the Orioles bullpen had only two guys with a WAR of 1.0 or above, and both had a 1.4.