First off I love the concept of the Upfront theme concept it has a slick and modern feel.
First some suggestions:
1. All your themes for Upfront have a decidedly tunnel vision approach to how it is laid out, pre-set pages and how templates are name etc. For instance, since you have no theme that is specifically geared toward e-commerce so I selected the Fixer theme because it has the slide option on the front page. But most all the templates are named and geared specifically to Construction
2. GIFs in the Upfront Basics Training go too fast to really see anything. Reference the GIFs at https://premium.wpmudev.org/blog/upfront-basics/
3. Icons are too specific for a particular theme i.e. in Fixer most are for construction which does not lend itself to other types of businesses. Now I understand that might be the case in a general sense but since you are driving people to select the Upfront as opposed to 'Legacy' themes I would think you would make them more universal in nature.
Now some issues:
1. When editing text I am unable to highlight text and change the formatting for that particular section of text using the 'Object' pull down menu. Say for instance if the text is in 'Paragraph' format and I wish to change it to Heading1 the selector does not work. It only inserts a hard return at the top of the text box with the 'Paragraph' setting. This is the case no matter which 'Object' I select.
2. When editing if User1 is working on a page and User2 wants to edit it. When User1 exits, the page is not available to User2 for editing for at least fifteen minutes and they will get the following message 'Someone is already working on this: User1', we sometimes get this message even after User1 has logged out of Wordpress. Or alternatively, User2 does not get the error message but they are still unable to highlight text and edit it. We have even gotten the message when User2 tries to modify text but they get the message 'Someone is already working on this: User2'