To monitor remote system usage, you could use a tool that outputs graphs to the terminal, like atopsar-plot. It is capable of plotting historic days with the --day parameter. Installation is easy, you just need atop, Python and pip. No configuration neccessary.
Full disclosure: I'm the author of atopsar-plot.
$ atopsar-plot --day 0 --disk sda --iface 0s31f6
%CPU_idle
┌──────────────────────────────────────────┐
1586.0┤▄▄▄█████▄▄▄▖ ▖ ▐█▄▄▄▄▄▄█▟█▙▄▄▄▄▄▄▄│
1532.0┤████████████▙▄▄▄▄▄▟█▖ ▟██████████████████│
1478.0┤█████████████████████▖▗███████████████████│
1424.0┤█████████████████████▙████████████████████│
└┬────────┬────────┬──────────┬───────────┬┘
09:57 10:37 11:07 12:07 13:07
%DSK_busy
┌────────────────────────────────────────────┐
36.0┤ ▟▄ │
24.0┤ ▟██▌ │
12.0┤▄▄ ▗████ │
0.0┤█████▄▄▄▄▄▄▄▄▄▄▄▄▟█▄█████████▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄│
└┬────────┬────────┬──────┬──────┬──────────┬┘
09:57 10:27 11:07 11:57 12:17 13:07
MB_SWP_free
┌──────────────────────────────────────────┐
8192.0┤████████████████████▙▄▄ │
8186.7┤███████████████████████▙▖ │
8181.3┤██████████████████████████▄▄ │
8176.0┤█████████████████████████████▙▄▄▄▄▄▄▄▄▄▄▄▄│
└┬────────┬────────┬──────────┬───────────┬┘
09:57 10:37 11:07 12:07 13:07
NET_iMbps
┌────────────────────────────────────────────┐
73.0┤ ▄█ │
48.7┤ ▗██▖ │
24.3┤ ▐██▌ │
0.0┤▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄█████████▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄│
└┬────────┬────────┬──────┬──────┬──────────┬┘
09:57 10:27 11:07 11:57 12:17 13:07
NET_oMbps
┌───────────────────────────────────────────┐
151.0┤ ▗▟ │
100.7┤ ▗▟██▖ │
50.3┤ ▄████▌ │
0.0┤▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄███████▄▄▄▄▄▄▄▄▄▄▄│
└┬─────────┬───────┬───────────┬───────────┬┘
09:57 10:37 11:07 12:07 13:07
atopsar
(which comes with atop) is a half-way there. It displays any wanted metric vs time. What remains is just to plot these time series. A general solution to this with a web interface would be cool to have. The accepted answer while great, doesn't go all the way towards a full solution.