i'd bet if it meant another delay in production many would disagree. especially over such a small change, and that is what a practical application of your suggestion would most likely necessitate. that's my take, suggestions are always a good idea. personally i'd just expect more than a perfunctory "cool", before suggesting improvements several ways in which it might be better, again all of which would slow down production.
i fully appreciate critique, but i also suggest context.
you supplied one, i, the other (imo). no judgement or hard feelings.
wasn't a design of mine or anything, i just know how bad people are screaming for these things and how little either design changes would actually help from my personal experience.
as to the sloping idea, with further thought it may be detrimental as it would (if i'm not mistaken) make it impossible to close it completely (again, could be wrong) which is a benefit for longer term storage. again, all my two cents.