Ways to add value when asked “What do you think would be biggest challenges for next quarter?”

As a mid-level engineer, this is a perfect opportunity for you to show senior engineer traits to your manager. In terms of how to do that, I have a question for your question:

Is your experience working on the team absolutely perfect?

I'm going to guess "No" - There is no team on Earth where absolutely nothing can be improved. I'm sure there's at least 1 thing your team does or has to work with that can be made at least a little bit smoother. Zoom out and figure out what these things are with some retrospection, and from there, you can propose solutions. This is a very common behavior I see separate the senior engineers from the mid-level engineers: The mid-level engineer is mostly focused on doing their assigned work well, while the senior engineer always has their finger on the overall pulse of the team, looking for strategies to uplift everyone, not just themselves.

As inspiration, here are some common culprits I've seen keep a team from being absolutely perfect:

• Overly hectic oncall - Solutions can be improving the oncall runbook, reducing false positive alerts, and improving the quality of your team's system overall.
• Slow build speeds - You can solve this with better code modularization and build system caching.
• Too much tribal knowledge - This means that it's hard to figure out important information without asking someone. Sometimes this manifests as a system blowing up after it's pushed to prod due to some legacy context someone forgot to bring up during design review. You can solve this with more mentorship amongst the team, better documentation, and a more rigorous system design process.
• Meeting overload - You can solve this by combining meetings together, deleting some, and moving more communication to async means like Slack and email.

Lastly, I recommend this discussion started by a mid-level engineer at Apple, which talks about how to come up with innovative, impactful ideas to bring to your team.

First thing I want to mention is that this doesn't need to be (shouldn't be) a once-a-quarter discussion. I'd recommend having a constant dialog with your manager about what challenges and opportunities are coming around the corner: next week, next month, and next quarter.

Ask a simple question: What more could I be doing? Do you have any feedback with my existing work?

Some ideas:

• Offer to take on tasks that align with your desired career path. Something like "I've noticed that there's not as much product definition for feature X, and I've been interested in working closer with PMs, so I'll start creating some milestones for it."
• Learn to anticipate problems and solve them without needing direct permission. This builds up a lot of trust if you do this consistently.

Ethan Evans talks about this a lot in his recent course, The Growth And Promotion Recipe - Magic Loop