It's never stated that ablative armor has to be replicated in order to work. I would consider simply integrating it into the existing design's armor paneling. It might seem nitpicking now, but you're early enough in the process that you have time to give the ship a writing pass and continuity keeping pass in addition to several art passes. Trek's two greatest Enterprises, the TMP refit and the Galaxy class, were heavily refined in all creative aspects until they fit a logically evolved art style from previous iterations, advanced technology extrapolated and innovated out of the old, and also fit the storytellers' bills.