I don't recall Lr ever crashing on me, but the list of things that annoy me about it is quite long. For example...
Very, very slow in loading zoomed-in images sometimes. No pattern to this I can discern
Inability to delete photos in Collection view. I mean c'mon, what is it with that?
Very, very limited Stack feature. More or less useless
No keyword editor
Total UI/UX confusion. For example, why, when I'm in library, and absent-mindedly hit R, does it switch to Develop? I don't like Modal, but make it Modal or not. Not some half-assed middle ground
No Save Workspace
Half-bakec dual screen support. When I double click on a thumbnail in my secondary screen, I want to see a full view (calling it "loupe" doesn't make it so) in that screen. I do NOT want my screen views to swap
Confusing, contradictory keywording tools
Filtering tools that look like they never went past prototype UI stage
No scope control for smart collections
Web module forgets all field entries when you change template. Really, wth???
Etc, etc, etc
The summary is that it looks to me that post v1, the only area that got any attention is Develop. And Develop is very, very good indeed. But then again so is ACR, and Lr should deliver more that a re-skinned ACR. Obviously, I'm also whining that "it's not Aperture". But the fact is Apple's marketing, product management, and vision with Aperture sucked infinitely more than any aspect of Lr.