Fair points. The wider economic struggle (in which Gandhi played only a small part)was massively important, it made running India impossible. Gandhi was not irrelevant, but he wasn't the only player, and I'd dispute whether he was the major player. To say that it was by following Gandhi's principles that Indian independence was won is simply not true.
You are absolutely right that the numbers of people involved are also absolutely critically important. Without the mass of people in support of any kind of 'anti-system' change, it wont happen. The more people involved, the less the need for any kind of violence. But if those fuckers are gonna start pointing guns at me and mine, and pulling on those triggers, then we need gund of our own to point back, or we'll be crushed.
And not havng a gun doesnt do anything to stop people being co-opted into the system they are trying to change, it doesnt mean they will stick to any principles any more than the person with an AK47.