For example, 'Ctrl + S' could be better for Save (where there is no shortcut defined) and a new definition for Split. Shortcut definitions should be set in Preferences
"File → Save" is not necessary because Quicken automatically writes all transaction changes and anything else you change in Quicken back to disk as soon as it happens.
If you need to create a "fallback checkpoint", you can always initiate a manual backup of your data file (keyboard shortcut: CTRL-B) to, for example, make sure you have a complete data file which you can restore from to fall back in case of problems.
