Why is Hinduism so Complex?

Somebody asked me why Hinduism was so complex and in what ways Hindu belief structure differed from the Abrahamic faiths.  This was the list I created: 

There are some basic differences in the belief system and structure between the Indian religions and the Abrahamic ones, notably: 

1. Hindu belief starts from an early agnostic position of accepting uncertainty. This is very evident in the Nasadiyasukta hymn of creation in the Rig Veda, Chapter 10.
2. The Hindu concept of “Ultimate truth” or “Brahman” is formless, abstract, non-personal, inclusive of the existent and nonexistent, and thus allows even an atheist to relate to. It is a non-deistic concept.
3. The early Hindu conceptualization of time and space is very different in that:  time is viewed in incredibly longer scales (almost close to estimations from modern physics), cycles of creation/destruction, space is viewed as expansive and not fixed, inclusive of the existent (matter) and non-existent (non-matter).
4. Everything in the universe, including all life, is viewed as “divine” or “good” innately, not as “sinners needing salvation”
5. Ethical code is not prescribed, but left to each individual to figure out based on their stage of evolution and own sense of their “Dharma”.
6. Path to enlightenment is again left to the individual to choose from among various approaches – Devotion, Knowledge, Work.
7. There is no common requirement across the traditions to adhere to any set of rules other than “follow your own Dharma”
8. The authors of the earliest scriptures are not known, and even early on, a vast array of scriptures (Vedas), counter-scriptures (Nastikas), and arguments (Upanishads) arose. Over time, these grew even more chaotically with the Puranas, the Yoga Sutras, and the main epics, Ramayana, Mahabharata
9. There is no one prophet or head, but numerous, so very decentralized by definition.
10. Has allowed embracing of multiple beliefs within its own fold (agnostic, atheistic, nontheistic, monotheistic, personal god, polytheism, animism, nature worship are all accepted as fine and not in conflict)

When you think of the above 10 items, it does allow for much greater complexity and less structure or uniformity – which is why I think the Indian system is very complex.