Right now your only option is to get a second Office 365 license and use a second email address to administer it for computers 6 thru 10. You'll need a third license for computer 11+.
Actually, you are the prime target for 365 licenses, with so many devices in your home. I'm on the flip side, with only 1 machine right now. So beyond my loathing for 365 CTR technology, 365 does not make financial sense for people like me.
Hey, don't complain about the 5 PC per 365 license limit. It is quite generous considering it previously was at best 3 computers per license for home use, so you would have needed at least 4 of the old licenses!
I have never heard of any suggestion that the 5 limit would be increased or removed. It doesn't make sense for MS to do it. Actually, looking in my crystal ball, I could see in a year or two MS would start to cut back on that count, as a way to get
MORE MONEY!
Using 10 or 11 volume licenses would probably be substantially more expensive than using 2 or 3 365 Home Premium licenses.
There is one more option. If you expect to use no more than 5 machines at a time, you could use "Office on Demand"
Video: Use Office anywhere with Office on Demand
http://office.microsoft.com/en-ca/videos/video-use-office-anywhere-with-office-on-demand-VA103984836.aspx
Go to Office.com. Log in with you account ID. Open any file from skydrive and a full copy of the App will run.
Office on Demand
http://www.winsupersite.com/article/office-2013-beta2/office-2013-feature-focus-office-demand-144117
Using Office on Demand in Office 2013
http://technet.microsoft.com/en-us/library/jj733592.aspx
Turn on the “Roaming” addon