Obviously we want Construct 2 to be 100% stable if possible. However usually it's difficult for us to do anything about it without a .capx project and some steps to reproduce a problem. If you send your .capx projects to me (firstname.lastname@example.org) with as much information as possible, such as what type of activity typically causes problems, then I can play around with your projects for a while and see if I can catch any crashes. If it is something system-specific though I might not be able to find anything - especially given some people say it's really solid, and others say they have occasional crashes, it suggests there may be something else on the system that is causing issues. Perhaps we can work around them, but again we need to figure out what they are, which can be hard. Also, having the latest drivers doesn't mean they're not crashing your system - drivers are notoriously crashy and pretty much all manufacturer's drivers have some kind of known issue at any given time.
Another thing (as mentioned) is opening too many tabs can use all your GPU memory, especially with large projects - keeping your tabs down to just the two or three you're using may help. We have a built-in warning at 30 tabs IIRC, but if you have an especially large project it may run out of memory sooner.
Anyway, if you send me some real projects perhaps I could take a look - we don't have many large-scale real-world Construct 2 projects to test with, so it might be helpful to us anyway.