So many thanks mala..... it really feels very nice to dig deep into tamil grammar and verses and come out with sweet words such as the ones many kind hubbers provided here. And you cleared so much of my doubts.......... For now we have shortlisted the following names

1. அருணிதா
2. தூவிதா or தூவிகா
3. நிரல்யா
4. விகிர்தா

looking to deep dive into sangam literatures further and come up with more options

Healthy nu meaning varugira maathiri some old tamil words? other than Arogyam, nalam etc., and tamil names for Goddesses, Lakshmi (other than thirumagal), Parvathi, Saraswathi, Kali