As a new player, I used to form a 6 character party and found it's nearly impossible to finish a play in time. But when I turn to a 3-4 character party, time is no longer a problem.
Maybe you should use bless & companions more to explore, in my experience, it means alomost all of them. If the check is too hard, you should consider such things:
1、be prepared to deal with monsters, mainly use Valeros、Amiri、Seoni, or Lini、Seelah、Merisiel when they got a weapon & can use their ablities,or even Lem、Ezren,when they got attak spells.
2、sent character to the right place, like Ezren to acadmey or Merisiel to jail, Amiri & Valeros to garrison.Lini & Seelah shines here because ther nearly fit in everywhere.
3、don't bother with the things not so important, let the check fail & let the card be banished, don't waste bless or companions on it.
4、you can also try a two character party, my suggestion is Lem with Valeros. let them go together. This combination can pass almost every check. Dealing with 40 location cards in 30 turns, time is definitely no more problem. Though it needs some other techniques.