LS614, is funny you asked cause right now I'm in the midle of my brainstorm about this. I like to keep the vintage look. Searching on the web I found exactly what I have in mind:
Before I install the engine kit, sometimes I gave few rides to my daugther in the bike front basket, we really have so much fun,
(my daughter & me)
but it was kind dangerous. After the kit was installed she was asking me when we'll ride together again, no way I'll put her in the basket to ride around. Then I start to look for ideas of a side car.
But the side car will make the bike more wide, for me is a negative point, I think I'll rather like a trailer, is wide but not that much. Something like this one.
Vintage trailer, yeap, that's it.