Construct supports Javascript coding in addition to its block-based approach. Javascript is an industry-standard language used widely across browsers, servers a...
We've done a ton of work to optimise event blocks already - I've written some past blogs covering work done on that (e.g. compiling expressions to JS). We've done so much that it's probably quite difficult to make any significant further improvements.
The blog post covers several major disadvantages of using a custom programming language. The benefits of JavaScript are so big I think it's clear it outweighs any benefits there may be of a custom language.