I actually found the "lets have sex" thing less funny in context. I thought it lacked... punch. I'm not sure why.

I loved quite a lot of Ianto's snark and comments but I felt in places he was getting awfully close to annoying and I felt him mucking about on the chair Beth was about to be strapped down to and possibly had her head explode was insensitive and kind of horrible. I like him being snarky but I also liked that he was a nice guy and generally fairly professional and I didn't feel he was either of those things particularly. But perhaps that was part of the theme of "Torchwood is actually really dark" they had going on? Or maybe it was just the writer. Time will tell (hopefully). Still too much Ianto is still way better than too little. And there was plenty of Tosh as well. :D