What New Features Would You Like Added to Blender 2.93?

For me i’d like a feature that when importing Objects with materials that have alpha Node Editor automatically connects the Image’s Alpha to the Principled Shader’s Alpha Node.

Another Is to have the Alpha Hashed in Default, Instead of Opaque

In theory, if 3D format of object imported handles transparency of material : it is already supported.
If you import a gltf file, you should obtain a respect of its transparency.
If you use Imaged as Planes addon, you know that is possible to obtain a material supporting transparency during an import.

That is not blender that does not handle that. That is the format of import/export.

About changing default for Blend Mode, that will not happen.
Opaque is used as default to make viewport/eevee more responsive. Any other alpha type has a cost.
So, that does not make sense for most of materials of most of objects that will not use transparency to have another default.

But that could make sense that when a node is plugged to alpha socket of a principled shader, transparency settings automatically changes to other defaults defined into user preferences.

That will not be made for Blender 2.93. When beta of release is announced, its content is already fixed. There will be no more feature added. Month of development until the release is spent on bugfixing and polishing.
Your wishlist can only impact Blender 3.0 or following releases.