If market attractiveness is already established, do not spend half the structure proving it again. Focus on the remaining decision: ability to win, economics, entry mode, implementation, and risks.

You can acknowledge the attractiveness as a given and move directly to whether this client should enter and how.

Strong structures adapt to what is already known instead of mechanically repeating a standard framework. If useful, this guide on case structure vs. case framework gives more detail.

If attractiveness is given, I skip it and go straight to can WE win + economics.