"sudo" is unavoidable since the installs are designed to go into /usr/local. The other option would be to require you to run as root/privileged which leads to the same issue of running an unseen script and just adds an extra step to the process.

It's possible to design the process to allow installs into other locations but that would require a fair bit of extra configuration (picking up the libraries, etc.) and testing. And you'd lose the service startups. It's something to think about if there's enough demand (and probably required for supporting Macs)