Haha, sorry read that wrong. Yeah definitely go with Tenebre and Phenomena next. Bird with the Crystal Plumage is great but I felt a little underwhelmed. Opera is good too. Mother of Tears is pretty crappy and not even in a good crappy horror film type of way, but like you I imagine, I watched it just because I wanted to finish off the trilogy.
Black Sabbath is my favourite Bava! Did you stop after the first story because you didn't like it? Also, did you make sure you got the modern re-cut, like a lot of horror films from that era it was cut to shreds by the censors. That first film is supposedly barely recognisible in it's cut form. It wasn't even cut because of gore or anything it only got cut apart because of the implication that the 2 main characters were in a homosexual relationship.

I'd definitely recommend to keep watching! You haven't seen the best of the 3 stories yet (you'll know which one it is when you've seen it! Sent a shiver up my spine.)
Was a little undewhelmed by Blood and Black Lace myself. Haven't seen Danger - Diabolik myself though have heard good things. A really amazing Bava film, though it's not a horror, is Kidnapped (aka Rabid Dogs)! It's like a cult midnight movie, reminds me a lot of Scorsese's After Hours actually.
There's also a Bava film which I haven't seen but want to. Saw a Bava documentary on SkyArts back here a while back and they were going on about Bava's influence and how many people have copied his style and they were talking about this film and several people were saying how Alien basically plagarised Planet of the Vampires. Apparently Dan O'Bannon (director of Return of the Living Dead) was one of the writers on Alien and so I imagine would have seen it even id Scott hadn't. Don't know how bad the plagarism is, but I want to watch it to find out.
Get the Bava boxsets if you can! I have both volumes, there's a couple of the famous ones missing, I had to buy Blood and Black Lace separately, but there's so many great and underrated classics on there. I don't know what country you are in/region of DVD, but there's 13 films on the 2 sets between them.
http://www.amazon.co.uk/Mario-Bava-Coll ... 133&sr=8-2http://www.amazon.co.uk/Bava-Box-Set-Re ... 133&sr=8-1