What powers or ability do these titles bring for different classes any other affect?

For a priest,

Chapter 1 : Inquisitorial Investigator and Inquisitorial Prosecutor

No noticeable effects for either titles except for slightly different dialogue in chapter 2.

Chapter 2 : Inquisitorial Judge

Able to conduct arrests and trial proceedings by speaking directly to the town sheriff instead of speaking to the town's inquisitorial judge. Dialogue in trial proceedings are fairly similar.

Chapter 3 : Curial Inquisitor

Able to recruit an Inquisitorial Investigator to follow you as a companion and fight alongside you.

Priest:
Inquisitorial Prosecutor: You can charge and arrest people directly without having to obtain the consent of your superiors first.
Inquisitorial Judge: You can sentence those convicted of crimes against God and King directly without having to present your evidence and conclusions to a judge.
Curial Inquisitor: You can ask for one inquisitorial investigator to aid you in your investigation.

Paladin:
Commander: You can enter the Hillbrandt chapter of the Brotherhood of the Righteous.
Master: You can enter the Glatzburg chapter of the Brotherhood of the Righteous.
Seneschal: You can enter the Alvaron chapter of the Brotherhood of the Righteous.

Thief:
Baron: You become the owner of the village of Asherbalt and can recruit one soldier to your party.
Duke: You can recruit one more soldier to your party and receive a house in Glatzburg (I believe).
Grand Duke: You can recruit one more soldier to your party and receive a house in Alvaron (I believe).

At each promotion, you also get some XP, 4 skill points, 4 attribute points and a certain rare item.

And if I'm wrong, feel free to correct me...

What the big deal of entering chapter hours is there any benefit in that?

Haven't played a paladin yet, so I don't know. Maybe you can loot some chests in there, or maybe you get your own cell in it (with your own chest in which to put stuff you don't need at the moment).