@Yepesnopes: Yes, Characteristic dice are more valuable than Fortune dice for a list of reasons. Yes, two Fortune dice produce both a greater probability for success and a chance for more successes when compared to a single characteristic die. At average characteristic levels (Like Str 3) the small number of Fortune dice involved in the exchange(2) make the transition of nominal effect, out-of-game mechanical loss smoothed out by the few mechanical gains. In-game it's a barely noticed growing pain. However when you get up into above average characteristics the cost of characteristic advancement becomes much greater. From 4[3] it can really be a tough decision to advance to 5[0]. 5[0] can do things 4[3] can't, in addition to being able to gain more future Fortune dice in that characteristic in total. The increasing difficulty to advance a characteristic was by the original rules illustrated by the fact that it cost more and more advances to gain the next level in a characteristic. That way may seem preferable to having to take on a statistical alteration(or partial penalty if you look at it strictly in terms of successes in the dice pool) but not only in my own experience but also in the experiences shared with me on sites like this, Players are not interested in spending those high numbered advances to increase their characteristics. This way gives them the option to do so at reduced advancement costs while eliminating fortune dice overkill, or to keep their 3[2] and work on another characteristic instead of paying the cost of trying to be so specialized. Kind of like the exponential curve in a point-buy mixed with a sort of off set level ajustment like the 'Bloodlines' in 'Unearthed Arcana 3E'. Maxed out Fortune dice in both Career related characteristics? Might want to diversify your career path. Or not, and pay the costs to really become focused and follow all related careers and have all related characteristics climb to their maximum heights. If that's the case, the player needs to keep in mind the characteristic scale. Roughly 1 through 6 with a few exceptions. That means theres more of a power gap than systems with a broader scale. There is a huge difference between someone with Str 3 and someone with a Str 4, not just mechanically but especially in in-game rarity. It's exceptionally rare for a human to have any characteristic score a 5. A 6[+] should be Legendary for a human, even at PC rank 5. Back to the out of game mechanics of it. In coming up with this I thought about these main points. 1-Fortune dice need to be limited. 2-In order to not run into a dead-end during career advancement Fortune dice need to be limited by something that increases. 3-Limiting the Fortune dice by character rank does not add up without other rule changes, some of which I think take away thematically from the careers, like letting them put Fortune dice into characteristics that are not associated with that career. 4-It seemed natural that the sub parts of a characteristic should be governed by the greater part. 5-With the limitations on Fortune dice being based on Characteristic dice in a corresponding Characteristic the need for that characteristic to advance becomes much greater, with the extremely steep advancement cost for characteristics this can put a dead-end in front of a character. That's why the cost of advancing characteristics is now included in the cost of purchasing Fortune dice. 6-With characteristic advancement now at a reduced cost, PC characteristics raise in level far too quickly. 7-'Resetting' the Fortune dice allows for a steady progression of advancements the reward the PC along the way instead of requiring them to accumulate several advancements before purchasing an increased characteristic. The problem that you are saying is that there is a sort of shift-shock. And there is. However the alternative is still available to the PC. Save up your advancements just as you would if you were trying to increase your Characteristic using the normal rules, then spend them in whole or in part between Characteristic dice advancement and Fortune dice advancement. The more they save up the smoother the transition. But no one's stuck with the dead-end with their career advancements.

Yepesnopes said:

You do change sheets. However, in order to change careers you have to fill up all 10 slots in the current sheet. There won't be any open slots on that sheet available to use any more. So, there will only ever be 6 open slots available at one time … so 6 is the maximum value for stats (excepting the aforementioned Ogre bonus which allows a 7 in a couple stats)