Glad you could make it. As to the flight feather, without assistance avatars can only fly to about 150 m (or so). An avi can go above that but very very slowly and then he/she will simply stop flying. My sky station, sky platform and holodeck are at about 600 m. So, to fly at that altitude you require a device that assists. I TPd everyone there, and if you step off the platform you fall LOL. There are a variety of devices to assist in flying above the 200 m and one free one is the flight feather.
When one leases land or owns land in SL, one also owns/possesses the horizontal space above the land. The reason that I have my sky station, sky platform and holodeck at that height is that it is out of the way from our main site, which helps to prevent clutter down at the main site. I work up there developing objects to take down to the CURA site. As well, one isn't bothered much up there by avatars simply wandering by. We are also planning to use the sky platform as our starting point for a May workshop...not many things up there to distract, just have to keep all the newbies from falling off LOL.
A side issue: The limiting factor for building on one's land are the number of prims one is allowed. Prims are the basic building blocks of SL. So, when one leases or purchases land it is the number of prims allowed on that property that are of ultimate importance. On the smallest lot, 512 m, one is allowed 117 prims. Our property is almost 12,000 m, which gives us around 3000 prims to work with.