I haven't ported this over to BBlog, but I have made a userscript which adds a randomize button to the loadout screen on battlelog. If you go to the loadout screen and click the new randomize button, it will randomly select an unlocked attachment/weapon/attachment. Note that it cannot (currently) select an entire random loadoutin one click, you have to actually click the button on the page for each attachment/weapon/gadget slot that you want randomized. When you're done, click save and the loadout will be sent to the game if it's open, and you'll spawn with it next time you die, or it will be saved for the next game you join.
I created it to allow the Say When Series onBigMooney06 and Nickbunyun's channels after the BF4 loadout screen changes, but I can't seem to contact them to tell them (or they're ignoring me :( ), so I'm posting it here for anyone who wants it to use.
The script page is at
http://userscripts.org/scripts/show/185841
You can install it directly by clicking on
http://userscripts.org/scripts/source/185841.user.js
To use it, you need the GreaseMonkey extension for firefox:
https://addons.mozilla.org/en-US/firefox/addon/greasemonkey/
Or the TamperMonkey extension for Chrome:
https://chrome.google.com/webstore/detail/tampermonkey/dhdgffkkebhmkfjojejmpbldmpobfkfo?hl=en