Agreeing and Disagreeing on Informal Talks/ Trivial Topics

In both formal and informal conversations, we can show people that we agree with them on trivial/ common topics, which makes the conversation a friendly one and keeps it going. If we happen to disagree with any of their opinions, tastes, etc., it is no offense to say so, as long as we do so politely, of course.
The simplest way to agree with someone is by saying "Me too" or "Me neither", but there are other options, too:

“I wouldn’t like to play chess tonight” 

               

Short Answer: “Me neither”

Short Answer + Aux: “Neither would I”

Full form: “I wouldn’t like to play (chess), either”

Disagreeing: “I would!”

“I’m a big fan of 70’s Rock music”

Short answer: Me too!

Short answer + Aux: So am I!

Full form: I’m a huge fan of 70’s rock music, too!

Disagreeing: I’m not!