In Hinduism, the core of our beliefs i think centre around, freedom.
That includes freedom of speech, freedom of artistic expression, freedom of worships, freedom of leading once life.
Many Hindus (Mostly ones who are well versed in scriptures), do not consider superstitious practices (Rat temple) as genuine form of Vedic Hinduism. But since there is a ethos of freedom within Hinduism, most leave those who believe in such things alone, as to each is own is the motto.
Every person has there own Karma.
As for "Idol Worship" (Murti), its used as a guide and form of concentration, its a stepping stone to higher knowledge, with Murti veneration a sense of devotion and Love is formed for that aspect of the supreme, then by study of scriptures the Murti is no longer required once one reaches that level of higher consciousness.
Ishwar does not punish, it is Love and compassion.
That Love and devotion is required to feel the emotional aspect of our spirituality, the Vedic knowledge come after and helps to rid the ignorance of attachment, ego, hate ect. ect.
Hinduism is a system, It can claim to be the longest surviving system because its main base is freedom and knowledge.
God in Hinduism is Nirguna (Without attributes) and Saguna (With attributes) at the same time, as Ishwar is OMnipresent it is everywhere, even in the Murti that is worshipped.
That is why in Hinduism we say there is only GOD, instead of there is only one GOD.
OM TATH SATH