I think the power "Harrowed Home" from the Harrowed Blood line has more use then just being a free mage's magnificent mansion.
it says that all time stops in the Harrowed Home as the user is not in the Harrowed Home where all time restarts in the home.
Some of the ideas i could use with it is to
1.put dead party members in to stop their body's from rotting.
2.as it a portal that you make and need to designate who can go in, you can designate a "bad guy" so he could go in, then get him by say bull rush or tricking him, so when he goes in, he gets stop in time until the user comes in, giving the party time if they need it to heal up and maybe take him some where.
3.Some one only got so long to live? stop him in time until you can do something about it.
4.Could keep a spell going in there and it last a lot longer.
5. unlike mage's magnificent mansion it is the same place so you can use it as a moving place to keep items, set up a lab.
6. could use it to keep a Clone of your self in there, and the body would not rot and if you die, you get send to your body in the Harrowed Home where time would restart. only down side is you had is the clone would be made if your not in there so you may need to grow the clone else where and move it, or just be in there a lot of the time.
only downside i can think of if anything is in there when the user dies then i not sure what goes on with the Harrowed Home like is it are all the things there traped in time for good, can other people free them or do you need to get the user back to live to save them and so on.