Moving vent pipe and adding a 2nd toilet

[JohnDee]

I want to move a 3"ABS vent stack over about 3' and also add a 2nd toilet (2 toilets back-to-back), and then re-attach to the 3" ABS drain stack below the floor. Does this seem reasonable or am I missing something important?

Thanks

 

[Jeff H Young]

I see nothing wrong with proposed change