Would 'determine' or 'decide' be more correct when talking about a target audience?

In the phrase:

It may be best for you to decide on your target audience.

would replacing "decide" with "determine" be more correct, and why?

Solution 1:

If you "determine your target audience", then you may be deciding on your target audience, or you may be analyzing your content to figure out who your target audience is likely to be.

Just to highlight it a different way:

• If you decide on your target audience, then you modify the material to attract the audience that you want.
• If you determine your target audience, you might do the "decide" thing, or you might analyze your material to figure out the characteristics of the audience you are likely to attract, and then fine-tune the material to that audience.

There's a definite difference there which is important in the context of presentation and salesmanship that I assume is the background to the question. In such contexts it's definitely important to be flexible about who you are targeting and not decide on a target audience too quickly.

Solution 2:

There would be contexts where determine/decide are interchangeable, but not in OP's example.

It may be best for you to decide on your target audience.

...means you are going make the (possibly reasoned, but essentially free) choice of what target audience seems best to you.

It may be best for you to determine your target audience.

...implies that your target audience already exists, and that your task is to identify it - by whatever means you like, but you don't get to choose the target audience. You find them.