Unzip to a specific folder

My version of unzip has a -j option to not create any directory.

So

unzip -j /path/to/file.zip

Will extract all the files into the current directory without restoring the directory structure stored in the zip file.

If you want to only remove one level of directories from the archive, (extract myarchive/dir/file as dir/file, not file), you could use bsdtar (which does supports zip files in addition to tar files) instead and its -s option.

bsdtar -xf /path/to/file.zip -s'|[^/]*/||'

Restoring permissions is a feature of unzip (from the man page, version 6.00):

Dates,  times  and  permissions of stored directories are not restored
except under Unix. (On Windows NT and successors, timestamps  are  now
restored.)

and there is no option to switch if off.

It might be that an older version of unzip did not support restoring permission, but investigating that route is probably more cumbersome than trying to change the latest unzip source to do what you want.

If running chmod -R is unacceptable you can take a look at using Python's zipfile library, it is easy to use and gives you full control over the way you write the files that you extract from the zip file.