Interestingly, Lisbon allowed for another 5 years of one commissioner per state, which as we have seen Nice didn't:

Article 17

4. The Commission appointed between the date of entry into force of the Treaty of Lisbon and 31 October 2014, shall consist of one national of each Member State, including its President and the High Representative of the Union for Foreign Affairs and Security Policy who shall be one of its Vice-Presidents.

5. As from 1 November 2014, the Commission shall consist of a number of members, including its President and the High Representative of the Union for Foreign Affairs and Security Policy, corresponding to two thirds of the number of Member States, unless the European Council, acting unanimously, decides to alter this number.
   The members of the Commission shall be chosen from among the nationals of the Member States on the basis of a system of strictly equal rotation between the Member States, reflecting the demographic and geographical range of all the Member States. This system shall be established unanimously by the European Council in accordance with Article 244 of the Treaty on the Functioning of the European Union.

And

Article 244

In accordance with Article 17(5) of the Treaty on European Union, the Members of the Commission shall be chosen on the basis of a system of rotation established unanimously by the European Council and on the basis of the following principles:
(a) Member States shall be treated on a strictly equal footing as regards determination of the sequence of, and the time spent by, their nationals as members of the Commission; consequently, the difference between the total number of terms of office held by nationals of any given pair of Member States may never be more than one;
(b) subject to point (a), each successive Commission shall be so composed as to reflect satisfactorily the demographic and geographical range of all the Member States.

Gah, trust politicians to do a crap job of specifying an algorithm.

When the capital development of a country becomes a by-product of the activities of a casino, the job is likely to be ill-done. — John M. Keynes