The bhavabalas have to be moderated using the residential strength of planets and its nature and only then you can arrive at the realistic strength of the houses which involves quite a lot of mathematical computations. If it were so easy to make astrological evaluations, anyone could have become an astrologer.
It would be meaningless to evaluate a horoscope just by looking at the bhavabalas which sometimes will have no correlation to the actual experiences in life. Because there is also an Anubhavayoga too which implies the extent to which you will be able to enjoy the benefits of planetary placements and this requires a high degree of logical and mathematical knowledge coupled with a lot of experience.
A powerful 12th house will reduce wasteful expenditure, losses and will help in the acquisition of spiritual knowledge, pleasures in bed and other significations related to the house. Speculation is another sort of gambling which will normally end up in losses or no profit at all. No one has ever made himself rich by gambling if you look at history.