What I think the rules should be.

[Veresy]

First of all, our punishments are set as is. That is all.


To answer your other questions:

HERE-You are ONLY allowed to grief abandoned structures or your friends if they tell you to do so for a reason.

You are not allowed to grief. Period. You are not allowed to remove abandoned structures unless you have the owner's permission.
If the owner doesn't sign on, then you can't ask them permission. Therefore, you are not allowed to remove their structure.

HERE-Being mean, rude, and offensive to a staff member.

This is already in the rules. 

Please read section 4 of the rules. 
Please be familiar with all of our rules.

HERE- You are ONLY allowed to use:
Optifine
Shadow texture packs

There is nothing in the rules saying you can't use either of these.