changes in Document Library template

We have site name Projects, and we have 350 projects, we need to create libraries to each project, so the first library we will design it, then save it as template, so we can retrieve it to create the rest of libraries. in the future if i want to modify the libraries, by adding column or removing, or even editing the metadata, so i have to make all these changes in all 350 libraries. my question is if we have a master template, that i can only edit it and all these changes will be automatically reflected to the entire site 350 libraries .