The two most common alternatives are 1) using some of the newer shells people have created, like Oil shell [0], or 2) using programming language like Python, JavaScript, or PHP.
The problem with using a newer shell is that you'll have to install the new shell anywhere you want to use the script. Meanwhile bash is ubiquitous. Unless you're the only one maintaining the script, you're requiring others to learn the other shell to maintain the script.
The problem with using another programming language is that they rarely have good ergonomics for doing what bash does: stringing together commands, command input, command output, and files. If you try to do that in another programming language, things suddenly get a lot more complicate or at least more verbose.
So I still use bash, but I recognize that it's strength is in running other commands and dealing with I/O. If I'm doing complicated logic that doesn't involve that, then I'll offload my work to another language. Sometimes that just means calling a python script from bash, not avoiding bash completely.
If people found that they work better by taking other approaches, the please share them.