The main differences with the final product do not concern the ending:
- In the intro Shepard was supposed to actually face a trial.
- Javik was supposed to be included in the main game. In one script he is also referenced to as the Catalyst (although later, in the same script, the Citadel is also revealed to be the Catalyst. Whether this was a mistake or a simple plot advancement it's unclear).
- The battle at Thessia was a lot more dramatic, Kai Leng was actually dangerous, and Shepard would end up severely wounded. Kai Leng could also turn the Virmire survivor against Shepard.
- There was a "retake Omega from Cerberus" mission. This is where the rumors of a future Omega DLC came from, I suppose.
-The battle on Rannoch had an additional outcome, with Admiral Xen enslaving the Geth.
-The encounter with the Illusive Man was different.
-Zaheed had his own mission.
-etc etc, you have the links, enjoy the read!
In any case your list confirms few things, like the cut content to later sell it as DLC and that the plot was weak from the get go.
Honestly I've played most of their games since the BG days and they never had really strong writing. It was mostly pleasant enough to keep you going with the occasional moment of excellence that stuck out of the otherwise contrived and many times ham handed average. When did they become the "masters of storytelling" I do not know... They did good stories... for a game. But not that good. And the irony is that the more they loudly advertised their "asum, immersing" worlds, the weaker the result became.
PS Is it just me or the actual word of mouth dropped significantly faster for ME3 than ME2?