When playing on VP or CEO difficulty the expansion class only starts with 2 claims, the same as the other classes. This potentially makes them not viable at these difficulty levels.

I understand you gain an extra claim once you upgrade to L2. But by then it's to late.

This could be balanced in various ways, reducing claims of other classes at lower difficulties. Or retaining the 3rd claim for expansion only at higher difficulty. Thats very raw. Alternatively on CEO level expansion could be forced to suffer early and snowball after L2, creating a higher risk/reward setup.