Cuntisuyu, lacked political and military power in comparison with the other 3 regions.
But Cuntisuyu, although the smallest region, contained many sacred places and was heavily connected with the religion of the Inca Empire.
According to Waman Poma, Cuntisuyu was the most important of the four suyu in priestly organization.
In the ceque system (a series of ritual pathways leading outward from the main plaza of Cuzco into the rest of the empire), Chinchaysuyu, Antisuyu, and Kollasuyu contained nine lines of shrines each, while Cuntisuyu contained either fourteen or fifteen of the ceque lines.
Maybe one of the main reasons why Cuntisuyu was so interconnected with religion is because of the Nazca lines located there, quite possibly the incas knew those lines, as Cieza de Leon was able to explore the lines along with other pre-inca ruins like Chavin de Huantar or the city of Wari shortly after the collapse of the Tawantinsuyu and most probably the natives were the ones who told him about those places. Just a speculation thou.
Also, pic related, the ruins of Maucallacta (old town in quechua, in the andes many pre-columbian ruins whose name has been long forgotten are simply refered as "old towns", there're 2 other sites with the same name just in that area), is located near the Coropuna mountain god, apparently the seat of Coropuna's oracle and temple in inca times.
The Coropuna volcano was a very sacred mountain god of the Cuntisuyu, the 5th most important mountain god in the Inca Empire according to Cieza de Leon, many pre-Inca and Inca ruins have been found nearby, including a 2800 year old temple, so that area was very important and sacred since ancient times.