Dunno about the finer B3 settings for DI etc... Download the Full Manual and FX Lists, along with the latest Firmware from the Zoom site, rather than just go with the Quick User or Getting Started Guide
But with the B1on the Amp Sim is just like one of the effects you can have off the 5 in chain... and i have some patches of just the Marshall Superbass at differing settings... (you can turn the Cab bit on and off)
The B1on doesn't really do 'Stomp Mode' like the B1Four and other Zooms... You can turn effects within a patch On or Off but it's more a Finger/Button rather than Foot/Pedal action.
Which is why i approach it more as a Patch 'n Play.... with 10 Banks of 10 Patches...
With only a 1/4" Jack out would a Jack to XLR lead or Adaptor be better to feed a mixer or for DI, or as the output wouldn't be 3 wire Balanced wouldnt make any difference... apart from the style of socket connection?