The question asks,
How do you prepare and handle an interview for a senior position that demands both strategic/business skills and technical know-how?
The good news is, you're right - your varied background has given you a lot of material to work with. As you're finding though, it can be overwhelming to know how to funnel and filter that into a series of sentences that will communicate your readiness to an interviewer.
Some considerations when preparing for an interview in this situation:
- Choose the right opportunities in the first place. You are correct in assuming that your background is powerful, but you need to make sure you're applying for jobs where it will be appreciated. To put this another way: When some orgs hire leaders, they are looking for an expert in a specific subject matter. It sounds like those roles would be a bad fit. Usually, the job description will be written in a way where it makes this fairly obvious: A software engineering management role where they want specific software engineering skills and experience, versus one where they're looking for more of a generalist who is a good leader. It's also worth noting that, in general, smaller organizations will appreciate a jack-of-all trades more than a larger org that has the bandwidth and resource pool to focus people on being specialists.
- Consider the downside to your background. As hinted in the first point, your "asset" of a broad background may be seen by some as a negative, since it implies a lack of depth in any specific role or field. Prepare answers to questions related to this, since even for the right role, interviewers may ask.
- I saved the most important for last: Prepare stories about specific experiences where your background and your skills were an asset. Rather than trying to memorize the entire list of programming languages you've been exposed to, or roles you've played, or a long list of "accomplishments," be ready to talk about specific problems, and what you did to solve them. Perhaps you have a story where, in a software engineering role, you were able to put on your "architect" or "analyst" hat and solve a problem that stumped others. You are basically claiming that you're a really effective generalist - which is to say, someone who can solve problems no matter the environment or role. Be ready to prove that.
Resumes and interviews that read like a long list of accolades or a collection of buzzwords will put people to sleep. Technical skills and years of experience are just the table stakes. Those things get you in the door. Stories get you job offers. Prepare two or three success stories where you can show off when things went well for you. But, prepare one or two failure stories as well, where you can show off something that went wrong, and how you learned from it. You're claiming that your varied background has made you a star performer, because you were able to learn a lot - be ready to show off that learning.
Again, it's not about memorizing a list of great things you've accomplished, it's about picking the right stories to tell, and telling them in a clear and engaging fashion. A great way to practice this is to prepare the story, then tell it to someone who isn't in your field and ask them how it made them feel. If they say "confused" or "overwhelmed," you need to cut back on the technical details and focus on explaining a problem and a solution.