For the basic options for a unique website the personal license would be enough.
The real only differences between the personal and personal plus license, is that the plus can have 2 accounts, so admin and 1 other and 20 domains and the normal personal license only 1 user account, so admin and 10 domains.
Personal plus also has the pro pack, which are some extra features, which can be nice but are not really needed most of the time.
Personal licenses are intended for hobbyists and small businesses, not for shared hosting.
You can run multiple domains and e-mail addresses for seperate domains, but you can't give every customer their own account to login in DA.
Because in the personal license there is only the admin account, so they can get to anything.
And on the personal plus license, you only have 1 extra account, so for 1 customer.
So unless you are the one maintaining all domains/websites and email adresses etc. for your customers, you can can't use a personal license.
So if multiple clients must have their seperate account, you can't use any of the personal licenses.