Collaboration depth
monday.com
One-or-more owner assignment, in-task comments with @mentions, color-coded status labels and drag-and-drop boards are the fundamentals, and the team-level views are real: shared Gantt charts, cross-board dashboards with workload and budget widgets, a portfolio template spanning multiple teams and departments, and agents that assign work by capacity and skill set. What keeps this under the top band is access: we found no public information on guest or client access or permission models.
Stackfield
Planning is genuinely first-class: four dependency types, automatic rescheduling, a critical path and a network diagram, with cross-project work through portfolios and Gantt filtering across rooms and room groups. Guest and External roles with free unlimited externals handle client access with sane restrictions. Capacity is the thin spot — the member perspective counts each person's tasks but I found no public information on a true workload or capacity view.