You can get decent Lutron Serena shade integration already just with the Lutron Caseta IFTTT service/channel. Again, smartthings wouldn’t know if you had used the wall switch, but you can certainly include the shades in other smartthings automations. There may be a slight lag because of IFTTT, but that usually less of a user acceptance issue for shades than it is for lights.
You can get a similar integration with the Logitech Harmony hub acting as the “man in the middle.”
So if we get Serena shades integration through the new official SmartThings/Lutron integration my guess is it would be about the same but with a little less lag. We’ll see.
Another alternative for window coverings is Z wave. Zebra Blinds is one Company that has a specific SmartThings integration and one of their employees participates frequently in these forums so you can ask him any questions you have about their products. 