The linkage between the scenarios was light so that it didn't get 2 prescriptive based on results. Each scenario had 2 objectives - a primary and a secondary. It was the successful completion of these objectives that determined specific things for the following scenario.
The villains we played against were -
The Ennead : I've never played against these guys before and DAMN! are they a tough nut to crack. Unless you're able to nullify their stacking abilities or deal out some serious damage then you're not going to get very far against them. Which is about as far as we got... It wasn't a loss but it wasn't much of a victory either!
Then it was Ambuscade : Far simpler to combat than The Ennead (as there's just the one of him!) but he's really tough. Success awaited us in this game though and we managed to take him down although he did take out 2 of us in the process - including Chrono Ranger who I'd been playing.
And finally it was Gloom Weaver. In this game I'd changed character to Fanatic and boy was she uber effective against him. We didn't defeat him in the time allocated but we did complete the secondary objective.
All in all it was a fun way to play the game and having the clock ticking really added to the play style of the group. After all none of us knew each other before we started to play.
Might look to do something similar for future times we play Sentinels!