Now when you create a new blueprint of any class it is named NewBlueprint. But there is a common practice to name blueprints as BP_SomeName. It is even advised in Unreal Documentation.
So feature request is to default name a blueprint as BP_BaseClassName. For example if you subclass GameInstance it will be named BP_GameInstance. SomeUserActor subclassed would be BP_SomeUserActor etc.
Also as I know it is common practice (at least in our company :D) when developing C++/Blueprint is to make logic in C++ and setup variable values in subclassed blueprint. So that would be very useful I hope.
Thanks.
PS: Also such naming can be applied to all types of objects, lik T_ for textures, SM_ for static meshes, I_ for interfaces, etc.
PS2: Also some settings for setting up that rules would be great. Using some patterns like BP_{BaseClassName}, T_{FileName} etc.
Hope you get the idea.