Yeah, I did too, except for the repetitiveness of the bosses and what not (aim for the head!). Steve was awesome though.
Sorry about the spoilers btw, but with how Krauser was in RE4, it really shouldn't be a surprise that he would think like that.
And for the extra missions, you just have to beat the last level in under 10 minutes... Easier said than done. I had to spam most of my grenades to beat the boss extra fast after a couple failed attempts.