This could be an issue with symlinks. I see that deploy.php worked for you, but you may also try
deleting the resources from
pub/static and seeing if the instructions from https://magento.stackexchange.com/a/64808/594 work for you. If so, then it may save you some time during development as it should be faster than running deploy.php.
I hope this will help
If you imported database from the server where secure connection (https) is enabled, you need to disable it in local copy of the database (because you probably doesn't have secure connection on a localhost):
bin/magento setup:store-config:set --use-secure=0 --use-secure-admin=0 bin/magento cache:flush
Another thing to check is any speed optimizer modules. I didn't notice my client had one called MagePow Speedoptimizer and it sneakily was moving the require.js from loading in the head section to the body which doesn't work well at all, so I disabled it.
There are other speedoptimizer modules too for Magento 2 that can cause this.