Usually, the most important thing for all devotions is that we may grow closer to the Lord.

Yes. Heaven is very real. In fact, it is more real than the world we see.

An alternative is a memorial Mass for the dead which does not have those explicit references to baptism and communion. This is usually not a funeral liturgy.

This is an old question that has been asked many times. The short Catholic answer is no. Tradition is clear that Mary never had other children after Jesus.

As to which of the four gospels is a good choice, my opinion is that there is really not one that is better than another. You can tell your friend to just start with one of them.

As sin increased in the world, nature rebelled, and atrocities among ourselves increased.

God did not make, ask or even suggest Judas to betray Him. It was entirely his free choice.

Mental illnesses are diseases, not sins.

This is a very good question. This means that the reason for Mary to be without original sin has nothing to do with preserving Jesus from sin, since He was God and was without sin anyway.

It would be wrong to interpret that God forces Pharaoh to be stubborn, and so engineered a catastrophic genocide for the Egyptian innocents to prove a point.