create a personal coupon for each customer that is

I'm not following you.
You want a coupon which amount is automatically applid to all the orders of a user ?
In that case, you should turn on the "auto load" option of the coupon. To restrict it to a user, you can create a user group in the joomla user group manager, attache the group to the user and use the access level of the coupon to that user group so that the coupon can only be used by that user. That will require the Business edition.

- Just attach a coupon to a user (i.e. have a list of users to select from with each coupon)

-> You cannot assign a coupon to a user. But you can assign a coupon to a user group. If you want to assign a coupon to a specific user, you can create a new user group, attach it to the user as a second user group. All that has to be done via joomla users/user groups managers.
Then you can select the user group of that user in the coupon.


- Have a list of categories to include with each coupon
- Have a list of products to include with each coupon

-> You can have one category/product assigned to a coupon with the corresponding options of the coupon.


- Have a list of categories to exclude with each coupon
- Have a list of products to exclude with each coupon

-> There is no option for that.