I had some ideas for a vault rpc so these may be handy to have in a dashboard - Vault RPC by iancoleman · Pull Request #153 · maidsafe/rfcs · GitHub
Everyone has basically covered what I would want (mostly I personally would want technical info about consumption of resources, a bit like htop) but I think in a broader sense @JimCollinson is hitting close to the target with his suggestions around safecoin info.
One widget I find extremely useful and is one of the reasons I am diehard xfce user (yes just for this one widget) is this handy unobtrusive cpu meter that shows 0.5s interval usage for 80 samples. Any time I use a computer without it I find it weirdly unsettling not seeing if the cpu is in use or not. It feels like driving blind.
From that chart I can see I have just finished compiling a binary on all 4 cores, and have one core still running a small ongoing job.
So maybe some of the unicode block elements could be handy if you wanted to try making this type of thing? Not actually requesting it, just pointing out what I find useful for dashboardy stuff.