While this post does give info on how to maximize your average damage per hit it is not really that useful because, after some point at least, your goal should be to max your crit chance above all else. A bit of CD is okay but consistency is really the goal. I'll leave this up though in case it's intersting to anyone.
For anyone who's interested I ran a calculation to best order to invest one's mithril in the two critical skills such that you get the most bang for your buck along the way. It assumes you aren't getting any other bonuses from skills, if you are then you'd have to adjust for the difference. I'm hoping it's easy to understand, basically for each point of critical damage invested in the left column you should have invested the number of critical chance points in the right column.
Hope it's useful, happy to discuss how I came up with these numbers if anyone's interested. Also, this is simply a calculation of maximum average damage per hit, if you think that's not the best benchmark then I'd love to hear your thoughts.