There has been a culture shift over the past couple years as the organization aims to mature. Across departments there is a trend of hiring senior people from outside rather than promoting people internally. Independent of whether this is generally a good decision, it is causing frustration among longer-tenured employees.
On the engineering side in particular, leadership has non-negligibly increased the level of required documentation, process, and quality, while also adding more total projects, and not adding sufficient resources. From my awareness of the wider industry, these things are not at all unique to Kepler. But that doesn't make it any less challenging to deal with.
While most departments enable you to use the unlimited PTO, there are specific groups that frequently have vacation requests rejected. The unevenness of how this policy is applied is a con.
The company's pursuit of defense work with the US government is unpopular among Canadian employees in Toronto.