sure, everything is fine: la vie en rose!
at the end, this is pretty funny: you finally arrived to the same conclusions I did one year ago in PLIP 1896.
one year! it was hard to recognize the obvious, right? 
I'm not going to use any new version of Plone until I can include my static resources in a sane way; and I'll keep ranting about it until the framework team takes this challenge seriously and start a discussion about ways to fix it.
BTW, have you seen this or I'll have to wait until 2019? a sane way to handle static resources for add-ons! check it, use it, learn about it, criticize it... but don't keep just looking at your bellies: there is a whole world out there with different ideas on how things could be done.
do you guys want to talk about this on the next framework team meeting?