You can change the default siri voice in the settings menu. just go in the settings menu then Siri & Search options voice. . choose any one from the 4 voices.
2. Dark Mode
Save your iPhone battery by switching to Dark mode option. To activate dark mode go to settings then display option and now select dark option. Dark mode is best in the night time.
3. Add lockscreen features
Go to settings , Face id & password and now scroll down to option allow access when locked. To activate lock screen function.
4. Turn off homescreen apps shortcut
Settings then Home screen and now select add to Apps library. now your new apps will not come on homescreen itself.
5. Turn off 5g if you dont want it
If you don't have access to 5g or wanted to save some battery. then you can turn off 5g by going into settings, Cellular-cellular data options and then voice data and select option LTE
6. Use Back button
To activate go settings- Accessibility- Touch - Back tap and now you can select the action and click option to perform certain activity.
7. Turn off location tracking
Apps can track your location. To turn off location for a specific app. go to settings - choose app- click on location and turn off precise location option.
8. Full screen notification for incoming calls
Settings- Phone then incoming calls now tap on fullscreen option. Now you will have old style full screen notifications for calls.