On another forum, a member made a very good observation.
With your first order, from any company, you can't really expect to get everything 100% right.
One company's density isn't another's.
You have to get used to your suppliers products and hone your specs with each following order.

A graduated hairline, in my opinion, is always a good option.
65% density or light-medium seems to be the general preference.

It might not be EXACTLY right for you, but its a start.
And you'll find it MUCH easier to work with a slightly incorrect density than what you have to do with your own natural hair currently.

There are ways of thinning out a piece yourself if necessary.
Don't let this put you off.