First, a nit-pick; incandescent lamps are resistive and not inductive
and inrush isn't a common component. But low voltage lighting systems
with a core and coil transformer is exactly what will pop a fast fuse.

I would use Anderson Powerpole connectors and strap the batteries down
with good-sized nylon ties, you can get quite large ones if needed. Or
you could heat-shrink some parts of the hose clamp. Also, it sounds
like the battery connectors you are using leave the connections
exposed, if so an insulated connector is suggested. If using crimp
connectors use Panduit brand or maybe AMP and NEVER use the cheap ones
that you see everywhere.

Anderson powerpoles will allow two batteries to be connected, but it
will be + to + and - to - and that might be less entertaining. I guess
if the batteries are at the same voltage nothing would happen.
Anderson uses a small roll pin to join two connectors together, I
really don't like the pins and let a little glue wick between them
instead.