Tweak the first is changing the way the userbox (that thing in the top-right corner of each post on my friends page) displays the usernames. Previously it just displayed the username and linked it to the journal. It now displays the userhead (the little icon of a person) as well, and links that to the user profile page in exactly the same way as links like boggyb behave.
Tweak the second is making the userbox not only appear on my friends page, but on the lastn and entry pages as well. This also means that when I've used a different userpic to my default, the one I've chosen will now appear.
The actual implementation is a bit ugly - there's no nice place to hook it into the existing Generator layout that I use, so I ended up copying the print_entry() function into my own theme. This means that I'll have to update it whenever the underlying theme gets changed or new stuff is added, but I can live with that. This also means that I can't use the existing Everblue with Greys theme anymore either (as you can only have one layout and one theme selected), so I had to copy in the colours from that as well. And in the process I seem to have broken the background gradient on the navigation strip.
But those are all things that can be either dealt with or ignored, and in the meantime my friends page is now even more how I want.