First, I'm very much in accordance with popova71, Seamonkey is a very powerful & complete tool.
Next, I do believe that the fact that Midori can't access 'https' sites is a big drawback that was left out of the original post.
I'm using Lucid Puppy 5.1 (or Lupu) & its default browser is Midori 0.2.2.. It's fast but comes without plugins. Have to add that I'm running this VAIO notebook from a home-burned live cd because it has no HDD. My memory inventory=512MB of RAM & 128MB from CFCard (where my 2 versions of FF await me every time I turn on the machine; in fact, it takes me about the same time as the modem gets connected to the net to install my PET or start the unpacked FF latest version.