I don't think you need to use 2-class scenario. People usually use this when they need to code a lot of busniess logic code at entity-side.
I use Adapter Scenario almost all the time and personally I only use 2-class scenario when I need to extend a lot my entities, and in my case that is very infrequent. Most of the time people have their business project and they just need to add few things to their entities (via partial class or CODE_REGIONS), for example: custom properties, calculated fields, etc.
Another examples is when someone wants to extend a lot the entities (a lot of custom properties, a lot of methods, override this and that, etc), but they want to keep a flat-version of that entities (for serialization, for example). In that case 2-classes may suit appropriately.
For the rest, I think the General preset should be ok
So if we are to stick to having our business logic in the BL, we should avoid the "two class" since using them is so reminiscent to Self-Service as it allows for having the business logic and whatever in the actual entity (extended) class