To address thus the actual question: Why am I a Christian and not a Hindu?
The easy answer, I believe Christianity to be true. Whether my belief is informed by my cultural background or not, this is what I believe, but that background really doesn't matter. To dismiss the validity of something on account of the background of the person espousing it, is anyway the fallacy of Bulverism.
For I see Sin as a visceral reality. There are real injustices, real wrongs, and I cannot see these as only conventions. Some things are absolutely evil, and some superficially good things are surreptitiously so as well, depending how they are procured. This seems clear to me. Christianity addresses this, in fact harps on it, and its central act is an act of Atonement.
Hinduism doesn't address this. It often falls into pantheistic fancy or process, or Divine perspective claptrap. If these things were true, then it wouldn't matter anyway if I played the Wager, as all was god anyway, or evil actions actually 'good'. Even the Bhakti cults fall into this trap. I cannot abide excusing evil. No, Hinduism fails to address the moral life I see unfold, and in a Paschal Wager argument vis a vis a three way bet, its position is not dissimilar to the atheist one. If I considered them equally, Hinduism should not be chosen, as a stated goal is largely to escape rebirth. Moksha is sought, which the other options would have another spin of the wheel if we had chosen wrongly anyway. The very fact that I am weighing this option, means I have not as yet been liberated, so I would be reborn regardless. So nothing is lost by not choosing it.