There might well be a good but angsty fic showing canon from Oliver's point of view. Where really, he's been fighting to survive for so long but now he's really just fighting to die an respectable death. And it doesn't work and it doesn't work until he's finally fighting with these massive self-imposed handicaps and picking less and less reasonable fights.

A couple of really fabulous short stories about Methos in the future being his cool, good-by-choice psycho-by-nature self, are:

"Days Forsaken" by jacquez h. valentine
http://www.dementia.org/~jacquez/writing/hlfic/days_forsaken.html

"Methos by Firelight" by jacquez h. valentine
http://www.dementia.org/~jacquez/writing/hlfic/methosbyfirelight.html