- Not making lack of wardrobe a way of bullying poorer kids and kids competing on dress.
In schools where there is no uniform, it doesn't happen. In practice kids tend to settle down into wearing jeans and a top and don't compete. Face it, if a bully wants to bully, having uniform is definitely not going to prevent it. Schools should address bullying at source.
2)Clear expectation on dress, not wasting endless hours on arguing with students and parents on whether an outfit meets dress code or not.
But the reality is that wasting endless hours arguing about uniform is precisely what schools do. By contrast, schools with no uniform waste no time because they don't care whether children's trousers are the right shade of black and don't have to nag them to put on pointless, uncomfortable blazers when they're hot.
3)Teaching kids to follow rules.Do you think it matters if military recruits don't have perfectly ironed creases and spotless boots? No! But it matters if they can't follow instructions absolutely when they are servicing a tank etc. Nearly every job has rules or protocals which must be followed.
Soldiers in the army need to be able to follow orders more or less unthinkingly because matters of life and death hinge on them. Self-evidently that doesn't apply to school pupils or to people in the vast majority of jobs school pupils are likely to end up in. Most jobs of any value require employees to use their brains, critical functions and logic: that means not following rules blindly because they are there.
An example of the stupidity of this sort of expectation: I worked in an office where people routinely stayed until the job was done or even came in at weekends without pay to do it. A rule-bound idiot turned up who started making a massive issue about people being 30 seconds late back from lunch or taking what he deemed to be loo breaks that were too long. Result: people started walking out of the door at 5.30 on the dot, shutting down computers mid word if necessary, and productivity fell through the floor. That's what comes of making people follow instructions "absolutely" even when they are clearly stupid or counter-productive.
4 Gives student a safe way of rebelling
That counters everything you've just said about students learning to obey rules. Children who want to rebel will do so all the more if you insist on stupid rules which make you look like a petty jobsworth, because they will have zero respect for you.