Where I work, we have a large cluster of CentOS systems. I have my own repository which I use to seed packages to all of the systems. There's only one type of package used (RPM) and it all works very well. Neither I nor the tens of thousands of people who manage large scale Linux deployments (in my case well over 100 systems) could do our jobs if there weren't standardized, easy package management systems like RPM for easy software deployment.
That being said, it's nice that there is choice in terms of what package management system you want to use. If for some reason CentOS and RPMs don't work out for me I could switch to Debian or Ubuntu and use dpkg + apt-get or some other combination of distribution and package manager (or even roll my own). This level of choice is wonderful, but I don't think you realize that you don't have to use all of the many options available. Pick one that works for you in your environment and stick with it. It's really not as hard or time consuming as you make it out to be.