Dreams

Technical

C style increment and decrement operator (++): +=1 doesn't feel right.
ImportError debugger: Sometimes an error in a library causes a simple ImportError with no hope of trace back.
Canonical packaging method or library: No more distutils vs. setuptools vs. wheel issue 99, workarounds are not solutions.
Canonical package installer: No more pip vs easy_install vs [...]
Short hand method for super: Feels wasteful to keep writting super(Class, self).method(*args, **kwargs)
Better stale bytecode detection: No more having to hand delete .pyc files after a git pull
Fix or warning for some quirky syntax: (,) or a = 1,
True class private methods/attributes
Builtin syntax, PEP8 checker: Something like flake8 in the interpreter
In-place sorting: Sort a list without creating a new list
Selectable sorting algorithms: No one single algorithms is a perfect fit for all cases (quicksort, mergesort, insertionsort)
Anonymous classes
Ability to freeze/compile distributable executables or libraries
Just like Unicode, default UTC aware date/time handling by default
Sensible built-in HTTP, URL and date/time libraries like Requests, FURL and Arrow
Get rid of if _name_ == "_main_": a Python module should be a script or a library, not both
Better default shell: autocomplete is a must have feature so is interactive method and attribute inspection
A case/switch statement, nested if elif else reduce readability, a dictionary of callables feels hackish