There was a post on twitter that the Starkiller base in The Force Awakens was based on the planet Ilam. A very commendable idea. As a way mechanism to provide power energy to a weapon of destruction bigger than the Death Star, it makes sense. To understand the background to this concept, we need to go through the history of Death Star construction.
The first Death Star took 20 years to complete. Lack of parts and manpower were some of the reasons for this, but it was also due to the difficulty of achieving the power supply devised by the Geonosians. It was completed at enormous cost, but the structural flaws were discovered by the rebels and it was shattered by a single proton torpedo. The designers were executed, and in order to keep the prestige of the empire from being lost to the public, the giant Star Destroyer was built, which in turn strengthened the military power.
Thus, the emperor conceived a plan to develop a large weapon of destruction in a short period of time. In short, he believed that the delay in completing it until rebel spies stole the plans was fatal to the Empire. It was essential to develop a power source that would make it easier than before. The idea of diverting the kyber crystals that had been hidden on Coruscant to power it was conceived. This would save a great deal of human resources, cost and time compared to creating them from scratch. Confident in his ability to carry out this plan, the Emperor personally goes to the Death Star to lead the Battle of Endor.
However, the Battle of Endor resulted in the Empire's defeat with the destruction of the Death Star. The Empire lost two Sith, the Death Star, the Kyber Crystal, and the Star Destroyer.
Thirty years later, it is believed that the lessons learned led the First Order to the idea of converting the entire Kyber Crystal region of Ilam into a weapon of destruction to power it. Was it Snoke's advice?
There is an episode in Clone Wars season 7 where Anakin and Obi-Wan discover a giant kyber crystal in Utapau. They prevented Grievous from taking it from them, and fearing that it could be misused by the CIS, they destroyed the crystal along with a CIS battleship.
What if they hadn't thought of "misusing" the crystal for Jedi purposes? It could be diverted from the beginning to power the Death Star under construction. If diverted, the Death Star could be completed before the end of the Clone Wars. It would have been a decisive factor in the Republic's victory as soon as the weapon of destruction was completed. It would be a promising weapon for a power-starved Republic.
So you may be wondering why they didn't use the Sith kyber crystal that they had hidden on Coruscant. It seems to me that it was a tactical and technical risk to boldly use the Kyber Crystal, a Sith legacy, without the Jedi finding it. Translated with www.DeepL.com/Translator (free version)
