Use day old slightly stale bread with dried moisture to soak up custard better.
Use buttery bread or milk bread to add flavor and hold up well.
Butter will make the pudding extremely soft and rich and melt in the mouth. Also, it keeps bread from becoming soggy.
Let the bread rest in custard to soak up flavor and moisture properly.
Add cardamom, nutmeg, dried fruits, and nuts for additional flavor.