Something occurred to me on the bus ride home.
Okay, Sephiroth wants to mindfuck Cloud in FF7, check. He kills Aerith to do this, and tries to make Cloud kill her first. But why? Okay, Sephiroth wants Cloud to suffer. He thinks making him kill Aerith is the way to do it? If Sephiroth really wanted Cloud to suffer, and Cloti is the intent, why not endanger Tifa? Sure, he was gonna kill Aerith anyway, but he made it a grand production to mess with Cloud's head. Seems to me if Tifa was the one Cloud was interested in, Sephiroth would target her too. But nope, he never shows any concern for Tifa at all.
I'm just thinking that could be significant - that Sephiroth shows interest in Aerith when it comes to tormenting Cloud and shows none in Tifa. Maybe he thinks Aerith's death would have a greater impact on the guy than Tifa's, that he puts a lot of effort into the former and never even considers the latter? If nothing else, it's curious that it never occurs to Sephiroth to try and kill Tifa too, rob Cloud of both his love interests.