Unfortunately, I've still encountered problems (of the game-breaking variety).
*minor spoilers ahead*
1. In the quest, The Moon Comes Over the Tower, I'm at the point where all I need to do is meet the girl (I forget her name, it's been so long) outside of the Lucky 38. The quest marker still points eternally to an unoccupied position outside the Lucky 38, rendering this quest unfinishable.
2. More importantly, my current story quest is For the Republic, Part 2, wherein I'm asked to investigate the Muertas within Gomorrah. The receptionist still doesn't have any dialogue options which allow me to advance the quest, nor do any NPCs within Gomorrah. And the quest marker points me yet again to an unoccupied position in the foyer of the casino. I cannot complete the objective of investigating the Muertas short of killing the casino staff unprovoked (which then prompts me to return to the NCR officer and lie - something my goodie-two-shoes character would not do).
Conclusion: Being the eternal optimist that I am, I'm going to assume that the 33 hours I spent on this broken game pre-patch corrupted my game file to the point where no patch can fix these game-breaking bugs. I'm going to write off that time as lost and start over on my good character (by now I would have been starting my cold-hearted opportunist character, but oh well). I'm going to assume that after 30 more hours, when I'm back to where I am now but with this comprehensive patch being in effect the entire time, I'll be able to complete these quests as they were meant to be completed. For now, I'm reserving judgment, and I'll let y'all know in a few weeks how that turns out for me.