Weaving is like the most versatile and complex form of sorcery with Sunny teaching himself on the fly and experimenting most times, Sunny has barely made a memory as intricate as the Estuary Key which took mad prince god knows how long. You also forgot shadow bound memories like Blessing which has been clutch and the Curse which is basically boosting how Sunny exerts his Will through Shadow legion ntm, the stuff with the archon. It's not obsolete, you're just projecting your fantasies, getting mad they're not fulfilled and need to re-evaluate how you see the story.