I think Cacti is great except for the fact that it takes hours to configure it. There is a lot that you can do with it but I find it a little overly complicated. A script collecting disk utilization recently broke on me (for no apparent reason), I spent 3 hours and got no where.
I would like a tool like Cacti but super easy to setup. I have some familiarity wit RRD so a little bit of manual work is okay.
To make this more programming related: An alternative to a different software package would be to develop something custom built. Has anybody attempted this? What pieces to you use to built which parts?