@ditusa , the article you posted mentions several times that balanced operation was developed to make super long telephone line runs possible and adopted by the pro-audio industry for long cable runs between the mics and subsequent electronics. Sounds kinda like what I said in my post.
Your article is also chalk full of vague generalities like this, "Balanced lines offer advantages even if the connection is only 6" long, although it is also helpful for longer distances."
While this may be technically true, so is saying that spitting into the ocean raises its overall volume of water. Any minute "advantages" a balanced operation has on a sub 15-20ft cable runs are, in most cases, inaudible and nowhere near worth the huge additional cost. Getting an amp that sounds great is priority 1. That amp having XLRs is a distance 4th place on my priority list.