So you are saying that the trained police are treating their firearms like toys as they are prone to more accidental/negligent discharges by virtue of them handling firearms more. Ok, no. But I can level with you & say that there is a population of gun owners who may treat firearms like toys.
I think that elongating the process could be good for the reasons you mentioned and bad for other reasons ie domestic issues in which women have TRO against partners or general issues of self protection. I’m all for instituting a training requirement if that training is provided for free.
One issue that I’m noticing that allows malicious people (in this case, mass shooters) to fly undetected is that for the most part, their criminal backgrounds are clean. Universal background checks close the private sale loophole but that’s it. Mass shooters obtain their firearms by passing background checks that don’t delve into anyone’s medical history. Maybe changing the way background checks are performed entirely would help curb bad actors. Universal background checks do not/would not cover medical history either.