Best way to effect part word searching by default
This sounds like a good approach and could be done using a twig filter on your search string.

Here are the first two lines of the example from the docs:

{% set query = craft.request.getParam('q') %}
{% set entries = craft.entries.search(query|customFilter).order('score') %}


In this example query is now modified by customFilter and can be updated in your Twig filter to behave however you like.