Outside cat / feral cats have had massive negative impacts on bird and small mammal populations. Particularly in areas where they fill an ecological niche that the wildlife hasn’t adapted to due to none of the local fauna being in that niche. Hawaii and Australia in particular have this problem.
They say that you can’t get a proper seal with a beard, but I’ve managed to do it before. I wouldn’t be shocked if it did. And if it didn’t a slight leak is may still preferable to complete exposure.
Like with engineering, the fewer components the better. Of course each flag still needs to effectively relay it’s message.
I think Canada has a great example flag. It’s only used two colors, stripes, and one unique shape.
Also something to factor in is how unique is your flag. The Ivory Coast will forever be mistaken for Ireland. Both are simple but added detail could have avoided this.
On #3 water filtration is often a very overlooked thing. I’ve got a Sawyer filter I set up inline with a hydration pack for when I go hiking. Water filters are so cheap and can have great shelf life, pretty much every one should have one.