We are trying out OpenProject right now because we realized Vikunja is not quite ripe for our current needs, but we still envision Vikunja to become scalable, flexible while staying fluffy.
There are some aspects we noticed in OpenProject that really could elevate Vikunja:
- editing properties directly in table view
- the task view which has the task details with indentation (tree structure as already present) and allows you to rearrange tasks, dragging them to become subtasks
- custom kanban views such as one column for each parent task / project with the tasks underneath and then maybe even swimlanes for an extra layer