I'm honestly a huge fan of the moves this offseason.
Carroll and Co. have gotten weak in terms of sticking to the Carroll philosophy. Too much autonomy was given to coordinators and Cable in particular, it seems, and Carroll is refocusing the coach roster in an attempt to get back to having a completely cohesive coaching staff. Everyone on the same page.
Solari is more traditional and can coach both zone and man blocking. As it was said above, no more "Cable guys" with minimal experience that he wants as a blank slate. Schottenheimer has coached some great rushing attacks with minimal talent and Solari, who is scheme-versatile, can work with Schottenheimer to craft a more balanced offense that can rush at will.
Schottenheimer offenses seem to emphasize balance, despite the absolute lack of talent he's had throughout his career. While he has experience as a QB coach and is fluent in gameplanning for the air game, he has proven his mettle as a coordinator who can provide a good rushing attack. Overall results have lacked, just as the talent he's provided with has. We'll see what he can do in Seattle with an all-pro level QB.
As for the defense, Norton is what's needed. He isn't a master strategist or play-caller, but he is a motivator of elite caliber and his guys will run into the fire at his command. That's what Pete needed, a guy to rally the troops. Norton's lack of proficiency X and O's wise lead me to believe Pete is reining in the defense and taking more control over it, while Norton is there to provide attitude and a voice consistent with Pete's vision for the D.
I love how Pete is changing the staff to align with his vision - as long as Pete gets back to his philosophy, and it is a WINNING philosophy, I expect improvement.