Did not go through all of that but from what I read it is a mostly true and excessive collection of information from back then.
You just seem to exaggerate on a few things like the time needed on leveling, on killing stuff while doing so, and so on (example: yes mage needed loads of mana, but you "only" drank all 3-5 mobs, not after every mob - you DID consider drinking before engaging a mob that potentially added 2-3 more mobs though).
The most "complex" mechanic (in terms of stats) that not directly reflected in the stats you could see was the chance to get a crushing blow as a tank (=prot-warrior) - which you most importantly had to gear against for serious raiding - non-warriors could partially achieve this if they had really REALLY good gear, especially from naxx40.
Overall though, what was imo the most limiting factor on raiding back then, was the immense amount of consumables (and time farming those or the gold for them) needed as well as the mostly non-existent knowledge on game mechanics and influence of stats on your character (caused by poorly statted gear especially on set pieces). I still remember proudly completing my dungeon set on my warlock. A few weeks later I realized how crappy that set was. My next max level character had a mixture of high level greens and low level rares/epics to easily maximize damage output.
I still wonder whether or not they want to revise the vanilla servers in terms of balance (at least stat-wise on gear drops) and material consumption for raiding.