I cast the chart for 2 January 1992, 2040, Detroit and get Leo rising, with a difference of 53’ of arc between the two charts. I’ve checked date and time as well as geographical coordinates. I am using the Lahiri ayanamsa; astrodienst must use another because all positions (for planets and cusps) are of higher degree in the zodiac (+53’) in my chart as compared to the one you posted. I normally use the tropical zodiac, which has a single standard as opposed to the several variants of sidereal zodiac (one of the reasons I don’t use sidereal.) Aha, astrodienst uses Fagan’s ayanamsa.
In this chart there is a clear and powerful predominance of Fire, for there is a stellium in Sagittarius [a stellium is comprised of a minimum of four planets, at least two of which are not Sun, Mercury or Venus] and Jupiter occupies Leo. Adding to the strength of this preponderancee (a stellium plus half of the planets) is the fact that, excepting Saturn who is independent in Capricorn, Sun and Jupiter mutually dispose all other planets, and furthermore Jupiter in Leo is singleton east – awarding him a superlative role in the figure. He is also the only retrograde planet – he’s stationary, and beholds a partile trine to Uranus. I take Jupiter to be the most powerful planet in this chart based on these factors. Jupiter is in Leo, a Fire sign, underscoring the preeminence of this element. [Sun is also quite powerful, based principally on the mutual reception/disposition as well as his important conjunctions, but Jupiter is brought into high focus.]
This is not a complete analysis of the chart, but an analysis of those factors that help us determine the relative strengths of the elements in the chart – clearly Fire. Preponderance – assessed here by: 1. Simple number of planets in each of the four elements, 2. Stellium, 3. Element occupied by preeminent planet, 4. Element occupied by sole dispositor [here by a partial mutual disposition, which is important enough to carry some weight] – is always a primary consideration in any chart. There are many possible kinds of preponderance and when any of them are present they always produce an overtone that influences the operation of the particular features of the chart (individual planets and so forth). This individual will tend to display fiery characteristics in most life situations. If we understand the characteristics of Fire, we can immediately make some general interpretive statements about this individual. In regard to your original question, what is important here are the principles used in ascertaining elemental strength, not the specific steps we took in the analysis of this particular chart.
Air and Earth are weakly represented in the example chart, each of these elements containing only one planet. But Pluto is the most powerfully angular of the planets (6°) and Saturn is independent in his own sign. Small and seemingly insignificant weaknesses can sometimes produce vital effects, as was the case with Achilles' heel.
The Water element is occupied by three planets. Both Moon and Venus are in an inhospitable sign and intercepted in the Fourth as well. Moon-Mercury squares powerful Jupiter; it is the only hard aspect in the map. Mars, lord of Scorpio, has no essential dignity – he is peregrine and beholds no major aspect apart from the cross-sign conjunction. We can see that the Water element is more likely to produce difficulties than not, while Fire is fundamentally favorable. Moon is lord of the horoscope and therefore holds power over the general direction and tenor of the life. The unfavorable last degree of Cancer rises.
I think it is important to ask ourselves, What is the function of the elements in the human psyche? Weak understanding of this and related questions yields weakened ability to interpret the chart. You may find Karen Hamaker-Zondag’s “Elements and Crosses as the Basis of the Horoscope” useful in exploring these questions.