'stronger' is the key meaning.
"..making the conceptual framework and its component ideas not only stronger, but also accessible to modification."
"...strengthening the conceptual framework and its component ideas, and as well making it accessible to modification."
Note: The opening words ('these misconceptions') are out of place in your text extract (they don't help) .... they appear 'at odds' or in disagreement with the text that follows. You should have left that piece out as it can confuse.