Is it better for a person who does not wish to pay more than the obligatory Zakat and a small amount of charity to leave Islam and convert to Christianity in order to avoid the punishment of the hypocrites, knowing that he cannot be an atheist and is deeply attached to God?

Whoever among Muslims loves worldly life does not abandon their religion, for they know that the bliss of Paradise cannot be compared to that of this world, and that true happiness of the heart lies in faith. Hypocrisy is not what you mentioned; rather, it is feigning Islam while concealing disbelief. Islam does not call for abandoning worldly life entirely; instead, it permits enjoying lawful pleasures, encourages using blessings for the Hereafter, showing kindness to people, and avoiding corruption, alongside performing obligatory duties like Zakat (definition). The important thing is not to be completely attached to this world and neglect working for the Hereafter, and to maintain moderation in all matters, for zuhd (asceticism) is abandoning what is of no benefit in the Hereafter.