Hinostroza is 30 and a known quantity at the NHL level. We don't need any more tweeners at the NHL level, although he's nice to have in the event of injury issues.
Kemell probably isn't that close to being called up and may not produce if he did get the chance, but at least it would be a look at someone new that has a chance to keep getting better.
I would definitely let Kemell get on a nice roll in Milwaukee this season, I wouldn't call him up unless we were so decimated by injuries that he had guaranteed top-6 utilization and a spot on the PP. There's really no point in just bringing him up to ride the pines or eat hot dogs. Which is almost certainly what would happen to him under Bruno.
I don't see any point in switching Jankowski and Hinostroza either. They're both going to do great in the AHL, and nothing in the NHL. Anyway, the main things the Preds need to fix are more systematic and getting some bigger name players producing, fiddling with the finer details isn't really going to make a difference.
I do think there's a chance Parssinen would clear waivers, and agree that Tomasino probably wouldn't. But I don't see any use in sending Parssinen back down. He's not going to get faster, and he's already a good enough player to be playing every day if they were willing to use him. More time in the AHL isn't really going to help him get better. They're both at the stage of needing more time in the NHL. Or a change of scenery if that's what it takes to get the time in the NHL.