1-Let Sergeants go to the Army War college.

2-Let Sergeants experiment with small unit tactics and give them funds to do it with, then let them write the manual.

3-Let veteran combat Sergeants go directly to OCS and be comissioned as officers without all the college degree bull####.

4- Instead of just giving troops a booklist to read...buy them the books.
Developing agility is a profession long process. So speaking as a non-military person, these are the sorts of ideas (adaptations) that that strike me as possibly contributing to fostering ‘agility’, with the first two relevant to the development of ‘strategic corporals’.

3) I think this is a good idea but the actual details I think are a little complex.
In principle, this should be manageable. After all, I believe I am correct in saying that there are ‘mustangs’ currently in the ranks of the US military, and past officers, such as Gen. Alfred Grey, who started their military careers as an enlisted personnel did very well as officers. So I would think it would be case of developing processes for identifying likely candidates and then providing them with the opportunities. Whether this would require them to obtain an undergraduate degree before being commissioned as an officer, however, is an interesting issue. Some form of additional education ‘may’ be required (though this may be dependent on the individual in question and precisely what is looked for in a officer candidate) or perhaps some form of additional training.