As far as I am aware, you only get three options regarding the scanning on an XPR5550, but I am not 100% sure as I am still learning the radio and CPS myself.
Selected - The channel indicated by the channel selector
Last Free Channel - The channel where the radio detects no signal on it
Last Active Channel - The last channel where the radio in scan mode stopped and unmuted to receive audio
Voted - The last voted channel where the radio in scan mode stopped and unmuted to receive audio
As far as the home button, I think that is set under Buttons menu, specifically the One Touch Access, and your setting should read "Home Revert" which is selected from the Mode dropdown, and then of course you select the Channel to act as the "Home" channel from the same row.
I don't think these two options work in concert with each other, however, the Home Revert One Touch should send you to the designated channel. One other thing with the scanning lists, try setting your Priority 1 to "Selected" this way the channel you park the radio on is the first priority in the scan list.