It's important that more people see officers and get the impression that they are there to enforce peace, not dole out violence -- while still ensuring they have the tools to maintain safety and order. Large, threatening military-style vehicles don't send a good message to people who are already scared for their safety.
I don't remember who said it, in relation to sports - "Look good, feel good, play good." I think how you look can absolutely affect how you behave.
People trained by the military to police occupied communities should not be allowed to act as civilian police in peacetime conditions.
The military's RoE are also very strict with severe consequences for violating. Contrary to what some think, soldiers are not running around shooting every person they see.
Study suggests ex-military cops are 2.9x more likely to be involved in a shooting if they had been deployed, and still 1.9x if they were ex-military but not deployed.
It's worth considering that people who leave the military to join another high risk of violence job may simply be violence seeking individuals, and that a randomly selected solider who was required to be a policeman would not show this effect. But given we can't really control that, we'd likely be better hiring fewer ex-military vets.
Another search suggests vets are over-represented in police jobs by about 3.5x their baseline rate