Are a girl's requests of her suitors considered wrong, such as asking about their prayers, about smoking, or their interest in singing and television, due to her fear of their lack of commitment?

You have done well in asking and inquiring about the suitor's religiosity and character, and this is an obligation upon you and your family. The Sharia (definition) has enjoined choosing a husband based on character and religiosity, for a woman is too weak to remain steadfast in her faith with someone of poor character and religiosity.

Thus, the most important qualities of a suitor are character and religiosity. A person of faith and good character will either keep his wife honorably or release her kindly, and he will be blessed for his wife and offspring. If he is otherwise, then he must be avoided, especially those who are negligent in prayer.

If the suitor does not pray at all, he is an infidel (kafir) and it is impermissible for him to marry a Muslim woman. He must be called to repentance; if he repents, good; otherwise, he is to be executed. However, if he does not pray with the congregation, he is a transgressor (fasiq), and it is permissible to marry him, but those who are more religious and of better character are more deserving than him.

The point is that this matter is permissible, nay, obligatory, and that refusing a suitor who does not pray or commits forbidden acts (such as smoking, shaving the beard, and listening to music) is a permissible matter.