I'm looking for an adjective that describes someone who is never at rest; they are constantly thinking of / planning to do something positive. 'Scheme' or 'plot' would work, but those two words have an inherent negative connotation.
I think the word you are looking for is enterprising. Entrepreneurial is also good, but the connotations are more financially focused.
You are looking to define two different dimensions
Cunning, shrewd, imaginative.
Active, activist, motivated, engaged.
A good leader is cunning dealing with adversaries, shrewd when interacting with allies and imaginative in treating the issues of society.
An effective leader is active in anticipating problems, activist in exposing and overturning ineffective practices, motivated in improving the conditions of society, and engaged in the efforts that would lead to the proper functioning of society.
Powerhouse - a highly energetic and indefatigable person.
- Dynamo (or human dynamo)
- Live wire
Powerhouse and Human Dynamo both stress the constant creativity. All the above have positive connotations.