I suggest closing this as 'won't fix' (or even the apostrophetically-challenged 'wont fix').  I'll leave it open for a while to allow others to comment.

I have some sympathy for the idea: I also think that the str/repr of a complex number would look better with spaces (and without parentheses (and with 'i' in place of 'j'))).  I've always appreciated the fact that lists are printed in the form '[1, 2, 3]' rather than the less readable '[1,2,3]'.

But there's a big difference between 'it might have been better if ...' and 'it's worth changing this'.  Tinkering with minor details like this from release to release just isn't worth the potential difficulties (however minor) caused to users as they have to adapt their code.  The current behaviour is perfectly serviceable.

P.S.  What's the tokenizer got to do with this?