Making up user audience?

I understand that, for someone who’s just starting to put together a portfolio without any “real” projects under his belt, made up projects and scenarios are acceptable pieces of work to include. Perhaps I should’ve asked this question before going forward with my current personal project, but while fabricating a portfolio-building project with made up problems and solutions, specs/requirements and features is supposed to be okay.

• Is it okay to also make up the results of the “pretend research” that was supposed to have gone behind it? I don’t mean reviewing analytics/stats/numbers.
• How about the more audience-engaging, interactive aspects of research like interviews and surveys?
• Stakeholder meetings?
• Do I make up the users based on my own educated guesses?
• Do I just look at the nature of the project and derive specs and requirements from these fictional users and stakeholders based on what I see as the current shortcomings/opportunities for improvement of the website or product?

My gut tells me it’s completely fine to do so, but I feel like it’s too easy to just conjure up scenarios and solutions. Is this okay?