I think it would be more worthwile to have a good selection of repair tools in initrd/initramfs. When /usr is not mountable or defect, / might not be mountable either.
In fact, that happened to a colleague of mine just a few days ago when he hosed his workstation's md configuration. /boot was still found by grub, of course, but nothing could be mounted. Any tools in /sbin were not worth a bit, we needed a rescue dvd. Repair tools in initrd whould have helped.