Alternatives for "layperson"
Solution 1:
I wonder if this would be more suitable in English or even User Experience SE. But anyway, try a thesaurus. This one provides links to other words so you can keep probing to refine your meaning.
What's more important, if it's a persona analysis, "layperson" is destined to fail because it engulfs too much in the user spectrum. I'd recommend supplementing with an array of demographic information or even a couple scenarios (sometimes, even a picture) so that your audience can identify with the personas. Just "layperson" may conjure too many different concepts.
Also, a user can be a layperson at many contexts. For instance, if you're running a website selling sailboats. The layperson can be innocent at using a computer, or a newbie to sailing, or a newcomer to buying things that cost more than $10,000 online. You'd need to specify that as well.
Solution 2:
You're going after kind of a weird requirement here. Usually a site will have a hierarchy of users such as Admin > Moderator > User
Sometimes there's a few other classifications, but each step up the tree inherits from User
and any other class before it.
Unless there's a real need to deviate from the standard, it's generally recommended to stick to them.