The ability to be able to create a swimlane by any of the fields configured for a project (or accumulation of projects), including the project names would make the boards much more flexible.
For example swimlane by project (if more than one project selected), or swimlane by version, component etc - would scan the fields, and provided number of unique entries is less than a fixed amount (say 10 or whatever is appropriate for performance) would allow that field to be selected as the swimlane filter.
This would work well for boards which accumulate multiple projects into one. Then, as new projects get added, swimlanes automatically expand. For example, multiple projects, each with their own sprints - an accumulated kanban board could have swimlanes by sprints, which keeps expanding as more projects are added (or subtracted).