Modern amateur language designers usually are not aware of decades of research and breakthroughs in old-timer's languages, such as Algol, Scheme, Common Lisp, Standard ML and recently Haskell. They miss the beautiful specialized syntactic sugars in Standard ML (for defining and calling curried functions), Octave/Matlab matrix syntax, and the beautiful Common Lisp's looping and SETF macros, which inspired Python's for loop syntax for iterable collections and assignment operator overloading. Instead of spending time to learn and understand pros and cons and nuances they rush headlong to implement everything from scratch.

Really smart guys, however, are trying to leverage old-school languages, to climb on the shoulders of Titans.

David Moon created the PLOT language that leverages Lisps http://users.rcn.com/david-moon/PLOT3/ , Rich Hickey did almost the same with Clojure. Scala has been a leverage of Standard ML, similar to Ocaml. Now Swift is trying to distillate Scala, at least in terms of standard idioms and syntax choices. Julia has been build upon the big ideas from CLOS.

Python incorporated lots of good ideas and bits of syntax and managed to balance the syntax and unify semantics and since 3.5+ earned reputation of a well-designed language (clear, balanced, complementing each other semantics from the Lisp world, and carefully chosen syntax). It is also famous for its culture.

So, for those who wish to change the world by developing a new language, it might be a good idea to look at Standard ML and its derivatives and try to relax some constraints and balance the syntax according to modern conventions.

I personally would prefer to start from David Moon's PLOT3 and, perhaps, try to marry it with some lightweight type-system based with optional annotations.

Btw, Haskell's choice of not mixing type information and function definitions and use annotations with its own DSL for types is a really big idea. It reduces cognitive load, makes code extremely readable, and in general, it seems, the best of both worlds. Python's optional type annotations are clever, but less elegant.