I agree. This will be hard to scale to an entire application, I would not recommend using this as of now except for very platform independent logic, but hopefully with new releases and more meta-programming (or perhaps meta-meta-programming) features more usage options could be viable.
it depends, Zolang doesn't care for this (but it should, and will later on) and just forwards values. So if you're transpiling to languages that have a first index as 1... then yes :'D
Originally this language was created simply for creating a sharable model layer which can have some embedded logic, so originally I wanted to keep non-programmers in mind while designing this as the model layer is the most basic part of an application and very easy for a non-programmer to understand the concept of.
But you can do (a + (b - c) * d) in Zolang as well, the choice is yours