Imo are earnings listed in most careers within the Core rulebook to low!
In the rulebook you define the Middle class as “working 20 hours or less a week”, but most careers only support the earning Demogrant: class!
An earning roll of “2+X Infinity dice(s)” is 2 on average, because 3 of the 6 sides result in “0”. And with the “Effect”, which results in nearly every case in a drop of the Social Class, this raise to 66.6 %!
Given the fact that most ‘hazard duty’ jobs, police, military (in any form), emergency response (medical and fire fighters), will clearly work more then this, the earnings of these and many others should at least cover the Middle status entry. Which means they should have an Earning rating of “3+X Infinity dice”.
Furthermore should/could at second career selection in the same career result in a promotion. This could simulated so, that every repeated career get an increase in the base earning, so that “3+Xdice” become “4+Xdice”.
While I, too, think that career earnings are on the low side of things, I think your math is off: The average value of Infinity dice is 0.5, so each die adds 0.5 to the fixed earnings value.
Additionally, social class and career(s) only determine your starting value; you can increase earnings by buying the Lifestyle Talent “Investments” or rolling/choosing some lifepath events. Thus I assume the earnings values are only meant as a very rough indicator for the kind of lifestyle a career can support, and rather should be seen as a game mechanical tool to give pc’s starting earnings some variability.
The Infinity dice posses 3 sides with a “0” result, 1 with “Effect” (which for earning basically is an additional “0”, and 2 sides with a bonus.
So a typical career with an Earning rating of “2+1 Infinity” posses a 66.6 % chance to get a earning of “2” (of this iposses one quarter of the rolls the possibility to change the social standing), a 16.6 % chance to get a “3” earning, and a 16.6 % chance to get a “4” earning.
The talent of Lifestyle I left to the side, because it’s irrelevant in this case.
The basic career earning, means the earnings without any bonus, should be support at least a basic line, here defined as “Middle Class” with an Earning of 3.