They could do these the same way that they do Warlock Invocations and just call them Martial Maneuvers. Fighters would have the same number as a Warlock of their level has invocations. Other characters would have a few, maybe none unless they took a feat to gain some. Some Martial Maneuvers would be class restricted (Rogues should be able to take Dirty Trick, but not Divine Deflection, etc.)I'm not opposed to it, but I think that the fighter manuevers need to be expanded upon and beefed up. Maybe level-gate (or require multiple SD for) some options and give more options so that at higher levels you're not simply picking the manuevers that simply liked less than the ones you initially chose.
If you are concerned about caster/non caster balance maybe anyone who can cast has their number of maneuvers reduced by the highest level spell they can cast.