your first question, it depends to how well is their knowledge about their own religion. if they truly understand hindu, they'll know that there's only one god which they omit in yoga, which "om". some sami (hindu priests) claimed that for those who have higher faith in god, they don't need these forms or idols to symbolise god. but for those who less likely to have less faith with god, they could use idols to help them focus in prayers.
your second question, the idea of having too many gods is not eligible in hindu. most of the stories regarding battles between gods are most likely to be between His messengers and devils, not god. but today's hindu, they would prefer to say that gods fought devil to win the light.
after many researches and readings i did regarding hindu, i found out that this teachings had been went far from the original teachings from the mouths of their own scholars. some scholars couldn't even translate or understand this concept and they are most likely to believe but not having faith.