For No. 1 No its a terrible idea just because you own a fc doesnt mean you should be allowed to own every medium and large in the game thats unfair to everyone else and personally I dont care about your fc's small social circle. There are also plently of smalls for your fc that didnt bother to try grab a property at launch.
For No. 2 I dont see why this should be implemented people buy smalls to buy larger later on putting a delay wont stop most people it will just punish those who where lucky to get a house right before patch especially 7 days why not 12 hours or something.
For No. 3 There are checkboxes if you have the two green ticks your good to go unless you have chocobo stables then just make sure you dont have any stored.
For No. 4 I mean they could make it clearer but the patch notes where pretty clear individuals where not allowed to purchase the plots and in red writing underneath it said transfers where ok (as they are giving back a piece of land which is fair stop being an entitled fc that demands a large)\
For No. 5 Sure I guess or you could just by a small there's still loads of them.

Kind Regards

Lupusregina Beta