It would be great to be able to manually control the order of static assets added via XML, for example if you are loading 5 CSS files you can set the order they load in.
At the moment this is out of a developers control, there are workarounds such as a adding an attribute but this still isn't very useful.There are extensions that add the ability to use so this is possible.
Some useful links/discussions:
- https://github.com/magento/magento2/issues/1821
- https://github.com/magento/magento2/issues/8406
- https://magento.stackexchange.com/questions/94769/what-is-the-proper-way-of-positioning-ordering-css...
- https://github.com/quickshiftin/mage2-ordered-assets
I have heard this mentioned several times, in this instance a third party module is adding some CSS which is loading before the custom CSS therefore overwriting it.