The first 30ish Eps play out like all the previous episodes in style, with mini arcs and lots of humor so there isn't much to say about those that hasn't been said about the previous episodes. The formula is kept in tact.
The major change to the formula is to the last 20 eps. These episodes are actually a really long story split between 2 arcs. There is no humor here, instead things get serious and dive into the actual main story behind Gintama. Expect a lot of action, more than all the previous episodes had, combined. During all this, the history behind some of the powerful characters such as the Shinsengumi, Joi rebels, multiple Space Pirate groups, and of course Gintoki.
After all that, the show ends suddenly. This is different than all the fake endings and no mention or insight into the next season, which is rather odd. How the show will continue with what happened is confusing as some of the main characters are technically gone now.
All the action and story was great, but hopefully the comedy Gintama will return instead of a serious Gintama, or at the very least a combination of the two.