My mame.ini file is like this...
Those paths are all in the MAME root dir. You don't need to type the full path, just the folder name.
Within my consoleroms directory there are subfolders for different software list consoles. NES, tg16, etc etc.
This setup works great for me. MAME properly detects everything. Non Arcade stuff is organized separately and the BIOS/Devices crap stays in their own separate folder.