Hello, and a big thumb up to the creators of Agenda. I played around an hour or two and got a Premium One Year license to support development.
Most of features I would like to see in Agenda are already on the roadmap or being mentioned in this thread. Nevertheless I’d like to list the ones which seems very important to really be able to use Agenda on my daily graphics and web micro-agency:
– Importing images and URL’s. The famous “Send to Agenda” services. See Bear app or DevonThink Pro. (Browser extension or background app).
– Link files. It is possible but only by adding the file to the Note. For large files residing on local disk (typically PSD files), it is useful to just link them (and save space on iCloud). An idea would be when dragging files to have the option to Link or Embed; accordingly an option in the Prefs, then a modifier key would do the other way. On the front side, a click would open and select the file in the Finder (URL scheme). It is important for a project management because the purpose is to gather all resources related and have a quick access to them.
– Connect to Address Book and Reminders. Useful obviously 
– Improve (and editable) themes. When you put side-by-side a window from Bear and Agenda, the first appears neater and more readable, thanks to the good typographical work they did. Agenda is also nice looking but some typo improvements might make it even better in usability. Definitely a plus: possibility to edit theme by choosing fonts size and color, background colours, checkbox styles…
–Display preview for URL as Apple Note is doing.
Thanks again 