Non Standard Levels - I'm an ATC and I'm happy to allocate them in the knowledge that if any one aircraft uses one then it may as well be all in - any protection afforded by using standard levels is gone and that's now the case across the Tasman and South West Pacific. If the driver airframe is sensible then strategic offsets are the only way to go - in my unit we allow up to 2 miles without any requirement to notify ATC.
Because it's my job to SEPARATE aircraft one from another, if I allocate a NS level to someone I only do it after considering what may crop up any time in the next hour to 90 minutes down his track - questions like where are the SE Asian carriers' overnight eastbound flights likely to be and am I going to be putting someone into their faces. Usually a quick check with neighbouring ATSUs is all that's required to settle the matter and that gives them a heads up on what's coming too.
With the automated exchange of flight data across airspace boundaries 30 minutes before the eta at the boundary, each ATSU gets the information about incoming flights without the ATC having to remember to make a phone call which further lessens the risk of having a head on at the same level.
Fitness for work - If you're not fit stay home, get better and don't bloody come to work and infect me. Ditto to having a hangover or other impairment - I don't want my name featuring in the report on your incident!!
Workload - when it all gets too much HOLD the traffic, don't accept departures, impose start up restrictions, in other words, use your loaf and don't allow yourself to be pressured - while you may think your behaviour in allowing yourself to accept more and more traffic will be somehow appreciated by management and your peers, it's got definite potential to be a career shortening move and could do a hell of a lot more harm than that.
And that's the gospel according to Moi - wishing a happy New Year to all you aviation people in the aiar & on the ground - have a safe 2010.