Basically, here's the deal:
If you want to do a job very well, and become an subject matter expert, and ultimately be respected for that, become an NCM. While you will on occasion be employed outside your trade, you'll always go back to it and be expected to be a master of it. As you progress, you'll do leadership courses and courses that will focus you on becoming an expert in your trade (ei...as infantry you start out learning how to be a rifleman, then how to lead a section, then how to master all small arms, then how to lead a platoon/make sure your officer isn't nuts, courses on how to oversee other infantrymen, etc). By the end of your career, you'll mentor soldiers on how to excel in their trade, and advise officers on how their ideas/policies will effect the soldiers.
If you want to enter what you can call a "managerial" class, become an officer. You won't actually become a master at your occupation: you're expected to become a generalist that can understand the many conflicting requirements of planning and executing military operations. As you go up in rank, instead of focusing on your occupation you will broaden your perspective (ei...learn how to command a platoon, then a combat team of infantry, armour, etc, then a mixed BG, then Joint or combined ops, etc). By the time you reach the end of your career, you really won't be an "expert" on your area, but you will know how everything fits together and bring that perspective into your "piece".
The other thing is leadership changes between being an NCM/NCO and officer. As a NCO, your leadership tool-box will be mainly of the inspirational kind. You'll lead by personal example most of the time, although there will be occasions when you'll employ a more consultative form of leadership. For an officer you start out with a personal kind of leadership style, but you will have to evolve it into a consultative form by the time you hit Major. It's hard to lead by personal example as you go up the chain, as your breadth of responsibilities increase. You'll still pull it out of your leadership "tool-box" from time to time, but not as much as NCOs do.
Just my 2 cents.