From a security perspective, is it better to fully patch 1.14.1 or upgrade to the latest 1.14.3?
If you apply the patch it should be easier and stable becasue on some minor version there were some extra (minor) change.
Maybe you can get your current version compared with a vanilla Magento 1.14.3 and check the modifications (I don't remember all those changes)
Although stability is important, my question is related to the security of the Magento platform and whether the iterative patching is any more/less secure than an upgrade from 1.14.1 to 1.14.3.
In that case if you apply the patches for your current version you will be as secure as 1.14.3.