A real complete astrological consultation is based on time, date and place of birth. Astrology is NOT what is generally accepted and spun by newspapers and the media etc. To make sweeping generalizations with sun signs is simplistic and irresponsible. The study of astrology is complex and must be learned like any other discipline. It must be treated with the respect it deserves as a powerful tool of understanding.
Tools are always dependent upon the astuteness of the craftsman and their application abilities.
There is one way that sun signs can be used in a positive way. That is by having the horoscope done properly and accurately and then placing the sun on the ascendant with its degree and sign as the ascendant. This is the solar chart. The solar chart can then be read just like a natal and is very revealing as far as implications and interpretations. In this way the solar chart can be used in conjunction with the natal house arrangement and adds powerful information as far as transits etc. as well once an accurate horoscope has been obtained.