whambam I see no problems with the current Gallery, File Manager and clock App.
They are pretty good. They were the actual default apps on real Android too like 10-15 years ago, so high quality, definitely. Still some users have reported issues with them.
The Gallery app makes it easy to accidentally delete the wrong or too many photos. Because the list of galleries and the list of photos in a gallery look just the same, and the confirmation dialog does not tell you what you are about to permanently delete. There has been accidents where users have deleted a whole album instead of just the last photo in an album, because the last photo was used as preview for the whole album. This is pretty bad UI, and could absolutely benefit from an overhaul or being replaced by a better app. Also scrolling direction is wrong compared to currently established standards, leading to some unnecessary cognitive stress.
The SMS app is probably most gravely in need of replacement, as it is even warning about being incompatible with this Android version, or being too old, when you launch it for the first time. This suggests it is just a matter of time before it won't run at all anymore, and would need to be urgently overhauled or replaced anyway. Better do that ahead of time.
The clock app has just been minimally adapted to GrapheneOS' rebooting if inactive policy. Only the default alarm ring tone works, and only if the alarm is set in the owner profile. This leads to much confusion for new users and not being woken up in the morning until one figures out where and how to set the alarm to work.
I think an overhaul would be good for users. But more importantly, it is going to have to happen anyway because of the apps being too old and going out of even the most extended compatibility modes.