It's actually fairly hard to make most of the Kansai passes pay off - you need to really travel as far off as you can to make them worthwhile.
As mentioned, the Icoca & Haruka discount ticket is worth looking at, as well as the 2 day Kintetsu Rail Pass, if you can arrange things to get the maximum savings. https://www.japan-guide.com/e/e2357_006.html
For your Day 3, the ideal thing would be to get to the tower just before sunset and watch the city turn from day to night. Actually though, the Tsutenkaku Tower is really old school - I didn't think the view was bad, but if you don't mind the higher ticket cost, the Abeno Harukas gives a far better view.http://goo.gl/XE5R94
You didn't specifically mention going to Dotonbori in the evening, and you definitely should - that is the best time by far. Another good choice for a view is the Cosmo Tower. I went on a weeknight and I had the whole floor to myself!
For Day 6, you could certainly add more. Osaka Castle has some good cherry blossoms but you might find the Kema Sakuranomiya Park to be better. And if you want to really see a castle, skip Osaka and go see Himeji Castle - it's the best surviving old castle in Japan - as well as an excellent cherry blossom spot. The Kokoen Garden near it is also extremely beautiful for its traditional gardens, and if you get the combination ticket, one of the places is pretty much free.https://goo.gl/65ZtRi
You could add more for Day 5 as well - Nara Park only takes half a day or so, unless you really want to go slowly.https://goo.gl/LfvWnL
You could also add in the Horyuji Temple, or see Uji, or add a few more hours in Kyoto. For your Day 7, all the places you mention are good, but none are famous for the cherry blossoms - you could walk down the Philosopher's Path, or go to Maruyama Park.https://goo.gl/knQtMg
For your last day in the morning, you could go see the Keitakuen Garden next to the zoo. It is one of the better traditional gardens in the city. Or on the way to the airport, go see Daisen Park in Sakai City.