I used Trello for a period of time, and the manoeuvrability (if that's the right word) of it was great - shuffling priorities around in a list, the satisfaction of dragging to a DONE column - so for tracking current tasks it was great. However, it was unusable for tracking and saving previously done tasks - they'd just pile up in a big DONE column, and eventually I'd have to archive it, losing all tracking. Have you solved this particular issue, or does accomplishment tracking not rank high in your priorities?