Hi,
I agree with sometimes manually setting the controls as you seem to understand how they work. But hey, automatic mode is always fastest when it works--as with Nikon or Canon cameras, lenses, and firmware. Plus, the Galaxy S10 is expensive and touts about the best smartphone camera, so...
First, can you describe the scene details or send an example of a photo you didn't like? Was there any uneven lighting or was the light dispersal fairly uniform? It seems that you understand the settings involved--so I'm not questioning your knowledge--just trying to understand the specific situation.
Second, do you use the focus locking and tracking setting since the last system updates (8 or 9)? When the focus object is right on target, the automatic setting values shouldn't be too bad--at least since the last updates.
The focus locking and tracking firmware is *supposed* to work along with the stabilization software to generate the best aperture, ISO speed and F-stop settings. This even seems to help when the focus object is *stationary* to your shooting position. Odd.
Would you also mind experimenting with this feature on and off and reporting any differences in the shot settings given your lighting and subjects?
Thanks!