Once you understand what periods, semicolons, and commas are actually doing, there is no confusion. In the same way an English writer doesn't get confused about when to use periods, Erlang's periods become invisible before long.
That's not to say they are awesome. They cause some issues with refactoring. Moving a bit of code might involve also changing its ending punctuation. This is also true in JavaScript, Python, and Ruby in list/map syntax. You just run into it more with Erlang since there is more of it.
Pattern matching is also one of my favorite things about Erlang, especially the binary syntax.
One example I particular like is the binary digest to hex representation[1]:
hexstring(<<X:128/big-unsigned-integer>>) ->
lists:flatten(io_lib:format("~32.16.0b", [X])).
I like Fred Hebert's (author of http://learnyousomeerlang.com/) explanation of syntax on his blog:
http://ferd.ca/on-erlang-s-syntax.html
At least the "template" explanation is most helpful to me.
> then there was just plain weird stuff like one-based indexes.
Interestingly, I don't think indexing is really that common in idiomatic Erlang. In other words when processing lists, one can split them into head and tail [H|T] or uses folds and maps.
So far, I agree with the note about 0/1-based indexing. It's just not used a lot. However, I find it pretty calming that indexes will work the way I expect them to, should I ever need to use them.
Now that I think about it, these two points (syntax and indexes) are somewhat petty things to point out about the Erlang : Elixir relationship, and I feel a bit bad for repeating them in the blog post. Things like protocols are way more interesting (and hopefully, are what drives you to try out Elixir). (-:
I like Erlang and I wouldn't say Elixir is there to replace it. I see a use of Elixir for scripting or creating DSL. Also it gets a huge bonus by running on BEAM. As far as internal design (and I am speaking as an amateur here), BEAM is far superior to JVM from the reliability and concurrency point of view. So having Elixir around is helping Erlang team, kind of like many see Scala and Clojure as a way to make the Java ecosystem appealing and exciting again.