Thanks a lot for the blazing fast reply VintageBazaar!
In general it seems to me, the transfer speed and even the cost of the creature transfer should not be too important, as those creatures are supposed to be pretty valuable, and the act of 'handing your creature to the new master' is not something to be taken lightly and done every now and then

I guess the choice of the best chain to keep creatures on, is mostly up to the ease of usage. The one which makes it easier for average user/gamer should be the most suitable - unless the Augmentors tech completely hides all the tech details from the end user - as in that case the ease of use becomes secondary, and security becomes most important.
Anyway, thanks for the info, and... keep battling!

But it can become problem if too many creatures get released. I know team said ICO creatures will be rare, but that does not say they will not create other creatures each week. This happens with the other game that uses XPY(and BCY)..they release new cards so often the rare ones dont really matter.