I don't think the changes should be made to the cards themselves, because then you're fishing not only for your divination seals, but also for specific cards. In your example, Spear or Spire would be far and away the best choice, and it would lead to this meh feeling when you're getting the other 2 seals filled out for divination.
I would like to see Divination itself changed. I like the new system but it is underwhelming IMO and it's because Divination is just another middling DPS buff. What I'd like to see is:
First of all, no more silliness with the scaling damage amounts based on number of seals.
All 3 seals - DPS buff (but bigger than it is now)
2 or more Lunar - Damage reduction
2 or more Celestial - Attack/Cast speed increase
2 or more Solar - Crit
Lord & Lady changed to Direct Hit buffs.
With this change I think it would give us a bit more choice and a bit more thought in how we handle or seals, as well as some flavor. Not being able to get all 3 won't result in you just hanging onto Divination until you have it or feeling like you wasted it. You just get a different effect. This also allows me to decide, for example, if I have a lot of casters I may prefer to go for more Celestial seals as opposed to getting all 3, or if I have groups that favor crit I can do that. I chose to preserve the damage reduction that originally came from Bole because it was the only one that was truly useful; if my party feels squishy I can choose to favor Lunar. Then, you still have all 3 seals kept in for your normal all-purpose buff. As for Lord & Lady, I changed them to Direct Hit more for flavor than anything; I don't suppose what they do really matters but I don't think resource regeneration should be involved.
Oh, I also kinda wonder if maybe there would still be a small damage increase along with the other effects? I'm not sure. The reason I like this change flavor-wise is because divination means to interpret the results of the signs you see, and if the results of our divinations are never different, what are we doing lol