I would love to be able to color code/fill the entire card based on which person this task has been assigned to.

Now you can do this with a picture per card, but a full screen of 20+ cards with 20+ photos gets distracting from the actual tasks at hand. And seeing 20+ cards in 5 or so colors (while using one color per person) is instantly more intuitive.

In addition one could still label each card separately and maintain the swim-lane option (compliments on this already elegant solution of swim-lanes based on label code/color).

With these two color options combined each card would have two color:

• main color for person to whom the card is assignment too
• label color on side, based on project, or priority in each vertical kanban column.