I don’t see “collectd” in your list. This is the list I have for my Omnia. I’m running v5, but I don’t think this has changed much since v3
I assume you’ve gone in to the Setup for the graphs, since some (most?) wont be enabled by default. One more thing to consider is there are two startup scripts related to this:
I believe luci_statistics takes your luci config files and creates the collectd config file, then should run collectd. But collectd error reporting is spotty at best. Make sure collectd is running and if it isn’t running, you can run it by hand with some debug flags.