A number of idols have been routinely used by my family in various upAsanas. A few are detailed below:
The sarasvati-series: The one on the left is the bR^ihad nIlA-sarasvatI, also known as bhaiShajya sarasvatI- worshipped by the secret offerings known as vAmadevya made as per the atharvaNa krama. It is a protector idol of the clan and the tassle of atharvanic bird feathers hang on the idol. One on the right is the viri~nchI-preyasyA, also worshipped as mahAsarasvatI.
The lakShmInArAyaNa pair: used for worship with the mantra viShNumAya, the sahasranAma vidhi and nArAyanArchana. The saura maNDala is used for the saura prayogas. Of course the other maNDala and its details remain secret.