I think our software can do everything your asking.
You can share a Password between Password Lists, but not if the password is configured for resets - select 'Copy or Move to Different Password List', and then you will see the first screenshot below.
For your other two requests, our Generic Fields on a Password List should help with this - second screenshot below. You can select different Field Types here, so hopefully one of the options available will be appropriate.
As stated by support, Copy & Link is available between as many lists as desired.
Add a custom field, add your 'tags'.
Make sure the field isn't encrypted so that it is searchable.
We've done this to make it easy to find passwords related to applications or services; and another custom field so we can search by server name.
It'd be wonderful to link security items through to hosts that exist in the system rather than using a custom field for it, but it's not a big deal.
A drop down field with a simply 'True' 'False' or 'Yes' 'No' values would achieve this. The first value you set in the field is the default value when creating new security items. Radio buttons would also achieve this - you can only select one radio button at a time, so its either true or false.
