Did you think the old app needed to be changed?

No the prevous one was perfect.

Yes they could have added features and fixed things. But the design itself was fine.

Mobile:
1) Make the Activity Menu List populate itself by pinning the users most actually used Activity Types. Currently you pinned a lot of activities regardless if the users has ever done any of them and therefore wasting space.
2) Add a word/date filter to search for activities.
3) Allow more overlays for the track graphs for example SUP (no speed overlay), or basically allow it for any activity with a recorded track.
4) Users should be able to select if they want a speed or pace graph (again SUP only supports pace, no speed on mobile app, both are available in the web interface)
5) Do a different evaluation if an activity is recorded as an indoor variant (GPS off), currently you still try to evaluate speed, distance, moving time based on GPS that of course all shows 0 as GPS was not used, better: if GPS is off in the activity, give us other stats, instead of showing us all those empty GPS based data-fields, like heartrate, movement time based on intervals (active / pause), steps per interval
6) Fix the the lap view for "other" that first interval is falsely labelled as "pause" followed by the real pause
7) Allow track trimming in the mobile app (don't repeat that annoying bug the web interface has where it zooms out to show the whole track once you move the slider to adjust a little bit at the end, making it impossible to see what you are doing)
8) Add some more cool Instagramable templates to share activities with friends, those work as advertisement for Garmin too.
Overall Web App:
1) Allow default gear to be setup for every activity- and subtype. Maybe even allow photos of the gear. And more gear statistics, not everything is measured with GPS, sometimes usage time could be valuable (overall time, active time, pause time for example climbing shoes).
2) Give us evaluation tools for strength training progress like: strengthlevel.com/

In my opinion, the new home page is significant step back from the old one.

• In the old page, I didn't have to think about what to display. The app did that for me. Any stat which had content was shown (with the option to hide a specific stat if I really wanted).
• The old page had unlimited stats. Now I have to pick and choose within some arbitrary limit.
• The old page was a simple list. No extra tapping to "show more", "show all", etc.
• The old app was just a vertical scroll. In the new one I have to vertical scroll or horizontal scroll depending on which view I'm in (e.g. "In Focus" or "At a Glance").
• The old page had more info with the full-width tiles for each stat. E.g. the Hydration stat showed my current hydration and my goal. Now I have to tap the Hydration stat, and the only place the goal is showed is in a tiny font under my current hydration.

I'm sure certain Garmin staff have their reputation, bonuses, etc. riding on the new home page being a success, so it's almost certainly not going to happen, but I implore Garmin to restore the old home page, or at least have an option to do so.

I loved the old home page. The new one introduces friction and complexity. Simpler is better.