Manjaro is very easy to use in all regards but I have some suggestions for you from my 1+ year experience of running a Manjaro spin called TROMjaro.com.
The main problem that I've seen users experience is with installing and updating stuff.
The Add/Remove software is very easy to use, yet not easy enough for most users I've noticed.
What seems difficult:
the popup dialogues and choosing of words: open Pamac and you see a list of apps. That's great. Click the "install" button and then "apply", seems very straight forward. What breaks the experience is the popup window called "transactions"
Although I get the logic of this window, for new users this looks a bit complicated. What is a "transaction" people asked me....and why is the "cancel" button highlighted? It means that we suggest them to click it? Users already chose to install that "app" and clicked "apply" already. Now they have to do it again. Another issue is with the little lag between clicking the first "apply" button and the "transaction" window, since the process triggers a refreshing of the databases. Click "apply" > triggers database refresh for a second or two > then it displays the "transaction" window. Some get confused and try to click again since they don't see an immediate response.
When users enable AUR they see a "build" button instead of "install" and that looks a bit confusing. Why not all have the "install" button?
When the install process is going on, the tiny bar at the bottom of Pamac is not very visible and users may try to close Pamac, not seeing that it is installing stuff. Would be best if the installation process will be as visible as that popup window with the "transactions" so that users clearly understand that they should wait for the installation process to be done.
Overall I would try to get rid of the popup "transaction" window and replace the "build" text with "install" for AUR, plus make the entire process take over the entire window so users are fully aware of what is happening.
Manjaro pushes a LOT of updates, almost on a weekly basis. I love that, but pretty much everyone I know who uses our spin, dislikes them. And that's because they are so many and so often. I do not know what to suggest in this regards but maybe to push updates less often so you increase the stability of the Stable version? For the past weeks I've seen updates ranging in the 700MB, almost every 10 or so days if not more often. People want to use their computers, not to update all the time. And kernel updates require a restart if you want to use the new updates, yet no one knows about that.
January 4 updates, February 6 updates, March 5 updates, April already 5 updates. This ia more than 1 update per week.
Also, the more updates, the more likelihood of errors during the update or after the update is done. I thought that Manjaro Stable will be a better Ubuntu in this regards, like pushing updates more often, but it is pushing updates so often that for some users it creates the Windows effect, where updates create a stress for the user. Some TROMjaro users pretty much hate the updates because they are so often, so many, and at times they break things here and there.
I do not know what to do about this but maybe Manjaro should reconsider their Stable branch and make it more "conservative".
Another issue I've seen is how the updates are "processed". Like the installation process, the update process itself is not very visible and people may forget that the system is still updating. Some close their computers without realizing updates are running. Make it super visible if possible and prevent computers from going into suspend mode or being restarted if possible. If users restart their computers or like it happened recently with one of our users, the laptop goes into suspend mode, this will break their system for sure. Speaking of which, would be best o integrate automatic backups before any update and an easy way for users to restore their system in case of a complete system failure after the updates. We use timeshift-autosnap for TROMjaro and although it is a primitive way to do this, it saved a few users in such situations. Would be fantastic to see a complete solution for backups and restore in Manjaro. Like if the system cannot start, users to be able to restore it in a graphical way to a previous backup.
Make the installation process easier by maybe removing the "transaction" window and/or making the process itself much more obvious. Second, the Stable version may need a more "conservative" approach and push less updates less often + make the update process a lot more visible and create automatic backups before every update.
Manjaro does a fantastic job and I love it. But these are a few things I observed over the past year of managing our Manjaro spin. Maybe some of you can take them into account.