Couldnt agree more with Kev, as I have $80.000 in live tournament winnings the last 12 months yet am only breakeven with buyins and costs.

With Sheriff I can not really agree. The question is, "Am I overbetting my bankroll?". Yes is he would be, hence he is making a mistake. But just because he does not intend to repeat that mistake, doesnt change the fact that he is making a mistake by overbetting his bankroll.
I am also into Sportsbetting and there is the so called "Kelly system" which helps you calculate your optimum bet size for each bet. Apart from your bankroll size, the other main factor is the "EV", the Expected Value. Do you estimate that your 10/11 shot has a 54% or 58% chance of winning for example?
I think this also applies to poker. Do you feel you have an edge over the field in the MTT you plan to enter? If no, why play it in the first place? If yes, do you feel it is significant even taking costs into account, and hoe big is it?
Of course there is also a massive difference in quality from one 5K event to the other. For example the CPC 2004 was so unbelievable weak in relation to the money (well yes I did finish unplaced as I got outfished

) yet other events are pretty strong. Another example is that I am happily playing $5.000 STTs at PP against "Joe Sixpak" etc. but would not be interested to fill the 10th on a table that already includes Marcel Luske, Humberto Brenes and 7 other pros for the same buyin. I am trying to say, pick your spots!
Finally, I advise you to maybe find a backer (or backers) that buy(s) a stake in you for a big tournament. As I think you have a solid reputation in the poker community you should be able to find someone.