That is the way the BSDs are developed and they're free software. If you want to you can pull the code and modify whatever you want. Let them get the thing up and running first, then see how the project handles external contributions. If they somehow fail to see the brilliance of some external contribution a fork will soon take over from where they dug themselves in, something which has happened many times over in free software land: Firefox (took over from the Mozilla Suite), Libreoffice (took over from Openoffice), Nextcloud (took over from Owncloud), egcs (took over from gcc, later became the main gcc branch), etc.