The central directory is a great feature of zip. Makes it easy to append to and to list the files or decompress individual files without decompressing the entire archive.
The actual horrible thing about zip is that there is no standard whatsoever for the encoding of filenames. So mangled filenames are common and most utilities don't even let you manually select the encoding if you know what it is.
There's also another standard called ZIP64 to allow for larger files (maximum 4GB in the original spec).
I was going to say that RAR is proprietary, but at least there's (non-FOSS) source code and good specs: https://www.rarlab.com/technote.htm