Whether a planet is cadent or succedent must mean something more than just "not as strong" as when in an angular house
The comment of mine that you quoted was mainly related to quadrant houses and their use in the original system of Astrology. In that system, quadrant houses were primarily used to determine planetary strength and gave a ranking of Angular houses being the ones that were most likely to see a planet expressing itself in the chart, for good or bad. Succedent or as they called them
Post ascensional followed in terms of strength and finally the cadent houses or
Declines as they were then referred to have spent their energy and offer little to build on. The post ascensional and Declines flank the angle, giving a set of three houses, referred to as an angular triad.
Now you are quite right that there's more to the houses than simply being one of the gauges of planetary strength. Two further factors need to be considered to understand the nature of the houses. The first of these is the relation of the house to the Ascendant and the second is a system now lost to modern Astrology, the planetary Joys.
Dealing with them in order: houses which are related to the Ascendant by a major aspect were seen as being 'conducive th business'. They are places where things can be done. Houses which are not configured to the Ascendant by a major aspect are
Averse or sometimes described as
idle It's difficult for a planet to express its naturn well in an idle house. This has the effect of empowering the first, tenth, eleventh, ninth, seventh, fifth and third houses as places for 'business'. The twelfth, eighth, sixth and second houses are idle and not very productive. Of these the eighth and second are succedent houses, the twelfth and sixth are cadent.
The second factor is the classical system of joys. Each planet had a place where it was able to perform best. For the Sun this is the ninth house, for Jupiter it was the eleventh and for Saturn the twelfth. These three are the diurnal or day planets. The Moon took the third, Venus the fifth and Mars the sixth. These are the three nocturnal or night planets. Mercury, which could be either diurnal or nocturnal took the first house.
Thus The ninth house, which casts a dominating trine to the Ascendant, symbolises solar things, such as the law, organised religion, and philosophy. It's a cadent house, so like all cadent houses it was associated with travel. Travel was generally seen as dangerous and risky but given the ninth's trine to the Ascendant and the Sun having it's joy there, it is the most favourable cadent house and travel is much less risky.
The Moon joys in the third. That's the house of the Goddess, of vulgar or pagan (literally) religion. It is also related to travel as it's cadent but it is related to the Ascendant through a sextile. So ninth and third became the houses of favourable travel.
Venus joys in the fifth and that house, which is related to the Ascendant by a subordinate trine, became related to Venal activities, such as enjoying yourself, sex, the leisure industry, and childen (the ultimate pleasure not just from the sex that precedes them but that you now have someone to look after you in your old age. All of these were linked to good fortune.
Mars and Saturn also joy in cadent houses. Mars in the sixth, which came to symbolise Mars like activities, such as accidents, injuries and wounds, and slaves, all things linked to bad fortune.
Saturn symbolised enemies, travel resulting in bad outcomes, prisons, hard work without reward, suffering, All activities that you took on but which went wrong.
Jupiter joys in the eleventh house and that house is also sextile to the Ascendant. The house is assoiated with Jovian activities, such as friends and friendship, civilised society, the administration of government, and being part of political life (in the widest sense - the Greek word for their city states is
polis, from which we derive our own words politics and police. Being a member of society in this sense was the highest form of human activity. Jupiter also symbolises your patron or sponsor. The person who helps you move on in your career.
Lastly Mercury symbolises the rational mind, communication, reasoning, the thing which makes humans different from animals (arguably). Mercury also has some duality to it, being a Hermaphrodite and also being able to be diurnal or nocturnal depending on circumstances. In the whole sign house system, which the Hellenistic Astrologers used for topical issues, the first house was the whole of the Ascending sign, part of which lay below the horizon in night but part of which had ascended into the light. The first symbolises the native, in Natal Astrology, body, mind and soul.
From the Ascendant to the Descendant going in the order of signs, is the lunar hemisphere. The realm of night, if instinct, of fortune and luck. A realm which it is difficult to control. From the Ascendant to the Descendant against the order of signs, is the realm of daylight, of reasoning and being a member of society.
From that system, we have developed our modern conception of houses but as you will see the essence of those is still heavily dependent on the original system.