I have found that it is very difficult to create a good trust list, even if you have only a small number of people on your list.
The
recursive implications are so big because people you trust enter on your Depth 0, so you trust them one level deeper than DT1 (assuming you've included DefaultTrust). A way around that would be to add them to an alt-account, and then add just that alt-account to your Trust list.
Having deep set to 2 makes sense if using default trust. However since a few years ago when I set up my own trust list I've been using deep 1. It's much more easy to handle.
So basically I trust feedback left by those I've added to my list and those they've added to theirs, but that's it.
I also have DefaultTrust on my list so as a side effect I only trust DT1 but not DT2. But the solution is adding DT2 users to my list directly if I miss their feedback.