HandsomeBob I only found and started using it maybe a month ago now? We're pretty small, its just me, so YMMV, but I think it could be easily scale-able. But the way I have it setup right now is one main 'Signage' board, (since we also have our furniture dept.). Then I have my Urgent/To-do list first, since it helps me to keep a more frequent eye on it. The next list is my 'Work In Progress', which uses a card for each current project I have in the hopper. For the job's card, I usually write a brief description, attach an order form (PDF, excel files) if applicable, any art or renderings, etc. You can also add comments. I then use the checklist to make an item for each stage of the process, design, cutting/printing, assembly, etc. If you have more than one person who may need to check on the status of things, they can easily go in and see, 'Ok, this is printed, waiting to be laminated..', or share art files, update renderings or order forms, etc. Or, you can have employees go in and mark each stage as complete at various work stations, or from the app even.
For larger projects, for example a 2-300 unit custom ADA interior package for a hospital, which we do frequently, I make an item card for that project under the 'WIP' list, but I also give the project its own list. This lets me to give each sign 'type/style/size' its own card, then we can use the checklist to track the progress. Granted this is likely unique to our workflow, but it helps to track progress more accurately and you can play with it and find something that suits your needs.
I then have a few other various list, one for Social Media to-do (which I am slacking horribly on), one for items I need to order that week, etc. We have a production coordinator and another manager who both deal with both signage and our furniture dept. I created a separate board for them to access that is more simplified, but is close to my WIP list on my board. Once a project is complete and ships or is picked up, then I move it over to the 'Completed WhateverMonth 2018' list, and that keeps track of all of our units built for that month. You can keep them for however long on the board, or archive them, and they will still be there forever. The second board helps me have my own little organized chaos on my board, but still allows those who may need to see the progress of things to do so.
As far as add-ons, I haven't tried any just yet. Hopefully this helps!