Polishing, may have some benefits, but unfortunately do not gives us a
long term benefits,
because a simpler code means smaller code, not good looking code :)

Nicolas, i don't want to discourage you. Your dedication is beyond
praises, but as to me, we have a lot of
code, which requires deep revision & ground-up rewriting and from this
point, spending a precious time with just polishing seems like a waste
to me.

However, if you like such kind of envolvement, i got an idea for you:
get rid of globals. :)
We are moving towards more modular system, and direct use of globals
(class names) instead of message sends
stands against it, because for example, if Kernel requires an service,
provided by package, which can be made optional, a direct use of its
classes should be discouraged. Instead all such uses should be
replaced by a message send, and leaving one gate point,
which will connect dependent package with one that provides given services.

Here's my list of most hated globals:
- Display
- Sensor
- World
- SourceFiles
- SystemChangeNotifier
- Utils
all of the above could be replaced by corresponding message sends i.e.
'self display'
so then, in case if we would need to get rid of that or extend the
model, we can easily change the semantics with minimal effort, in a
few places, instead of many.
For example, 'self display' could  be changed to answer a display,
local to particular morph & its world instance, and so, potentially we
could use many displays simultaneously.




-- 
Best regards,
Igor Stasenko AKA sig.