1. Crimp, solder, or both?
Solder, every time. If solder gets on the connector surface then you're doomed so I normally solder the insert with the wire up in the air so the solder can wick downwards.
2. Roll pins, glue, or
Roll pins for automobile applications, for everything else I just leave them out.
3. Tie wraps behind the connectors, yes/no?
No, never needed them.
One final thing. Most of the colors manufactured by Powerpole are fine but the brown is terrible. Even in decent light it looks very close to black so I ended up painting the shell with light brown model paint.