Note I am the co-founder of Wingware, makers of Wing IDE for Python
Wing IDE has syntax highlighting for Python and many other languages and a code completer that uses both static analysis and live runtime state when available (such as when the debugger is active or if you're working in the shell). There is also a Source Assistant, which gives you call tips, documentation, and other information relevant to the code you click on or are typing.
You can goto-definition on any symbol and also use the Find Uses tool to find all points of use (and also refactor to rename, move point of definition, etc).
The debugger includes some advanced features like conditional breakpoints, an interactive Debug Probe that work like a Python shell in the context of the current debug stack frame, and the ability to watch values by symbolic name or object reference.
What's missing from your list is that the debugger doesn't support IronPython.
You can get the somewhat simplified Wing IDE Personal for $45 but it doesn't have all the features I mentioned above. However, if you are using the IDE for coursework or thesis work, or for unpaid open source development, you can get Wing IDE Professional for free. See https://wingware.com/store/free