Lisp-like languages are too basic and theoretical to be changed dramatically. Grammatical changes (I do not mean to just change the names of commands) would just not fit the functional-programming theory behind them. But
But the fact that there are languages like lisp shows that "changes" were already made to lisp anyway. In other words, there are languages made by people who were inspired by lisp or it's theory behind it and made a in-a-way similar new language.
There are also a lot of languages inspired by Python. E.g. Julia, CoffeeScript, etc. which would form their own family of whitespace-sensitive object-oriented languages.
I think, fundamental basics of a language like Python will never really change. Python is object-oriented and therefore has similarities to C++ and Java but it's dynamic and therefore also similar to a lot of script languages.
Well who actually cares about languages? What counts is the purpose: French is similar to Latin but girls who understand French are way hotter ;)
Greetings from Europe.