Most RQ3 campaigns I have played in had some common magic (Spirit Magic in RQ3, Battle Magic in RQ2), if only for healing.
A scenario without the Heal spell might be over very quickly, as RQ combat can be quite deadly, especially against large/strong foes, or those with big weapons.
Having a Healer in the party might help, but only if the healer has not been injured. Also, RQ3 Spirit Magic is quite costly in terms of magic points, so a healer might only be able to heal 2 or 3 wounds per day, without magical support (MP Storage devices, bound spirits etc).