Its better than what Im getting (-32601 Method run_cmdline not supported.) 
Are you on windows? CLI access isn't available on Windows. It may work over RPC.
Im guessing one word seeds arent very secure then . 11 bits of entropy for a word? Im guessing thats to prevent underflow?
. 11 bits of entropy for a word? Im guessing thats to prevent underflow? It's 11 because the default dictionary is 2048 words (2^11). If you use a larger dictionary you can encode more bits. You can replace the default dictionaries with your own if you like. Here's one with nearly 9k words. It's a combination of the electrum dictionary and one I downloaded from the EFF's site. On linux you can replace the Electrum dictionary in /lib/python3/site-packages/ele colctrum/wordlist directory.
Ah thats quite cool. I think I have every word in the Collins English dictionary somewhere so thatll be interesting to try...
Is electrum happy to go over 256 bits of entropy?