I think if you keep the unstoppable ability in a future game you should rename it and give a clearer description. I also think allowing the baddie night kill to be unstoppable is still too powerful. It pretty much negates too many goodie abilities (i.e., saves, blocks, "can't die while xxx is still alive", etc) Also, having the ability tied to a role that was non-targetable makes it very powerful. There is no way for the goodies to get rid of the ability, they have to wait for the baddies to use the van to target one of two roles.
I liked the default lynch rule but I think it should have been an additional lynch instead of negating the day's vote. It ended up being a punishment to the goodies that were actually participating based on something well beyond their control. But I do think that simply killing the inactives is a good option, especially if there aren't enough people as backups.
I liked the D0 start but it really needs more participation. I was really worried that we'd end up with a tie and at that point, I don't think enough people had read the rules and understood the implications. But I do think it is a valid alternative to starting with a night phase, I think it'll just take a few games for everyone to get used to it.
I think the parcel created more confusion than was needed. You already had inactive penalties so I'm not sure the parcel added much to that end. I think the only way it would work well is if everyone playing is in the same time zone. As it stands, it is way too easy to pass the parcel to someone in a drastically different time zone knowing that they won't notice it for several hours.