The reason people pick both an SSD and a standard platter drive is to have the larger cheaper drive for application and file storage. If you don't need that, then you can just get a 256 or 512 GB SSD and not bother with a standard drive for applications, but you may want to keep files on it to keep wear on the SSD lower. Remember you also need a backup drive for your files. So install the programs on the SSD, and movies, photos, etc... on the standard drive, with a second backup drive also, maybe an external.