I have certainly run many different Keeper teams. Some are similar to yours and Emos. I like the one TaliaParks posted, too.
Keeper’s Necromancy trait, sadly is not enough for soul generation so I mainly run him with Valkyrie. This is not an issue with the card. Frankly, I hate running teams without Valkyrie because soul generation comes to a standstill. Perhaps this will be addressed in the future. Even so, here are a few with some comments:
Hero, Valkyrie***, Giant Spider***, Keeper of Souls**
This combination, as noted, is excellent. I have played with a lot of weapon and class combinations. Some notable ones that work well are Necromancer using Creeping Death (buff death mark please =p), Sorcerer using Burning Scythe, or Warlord using Gard’s Wall (For some reason I always like Proud Banner with the latter combination).
I used to always play with Templar builds because I enjoy the card so much. Once traits were released, Armored made this quite nice:
Templar***, Valkyrie***, Giant Spider***, Keeper of Souls**
As Emos mentioned, Green Slime is a fantastic choice and of course, Abhorath or Hydra. I go with Vampire Banner when using Abhorath.
Some alternates for Keeper make for interesting teams. Psion works well here as well. Interestingly, Both Giant Spider AND Valkyrie feed into Psion. I like Banner of Progress for that team.
Keeper and I are so close our snapchats are like:
However, I must admit to having a SIDE BFF!
One of my strongest Templar teams using this composition is placing Infernal King in the final slot. I played with a lot of Infernal King teams and there are good ones, but I enjoy the Synergy with Templar transforming greens so that the Infernal King can chuck them back at the other team as skulls. You have to carefully watch your matches (brown and red, and skulls to green) to ensure that you get an extra turn from one of them; otherwise, this can blow up in your face. Finally, I use Divinion Banner for this combination.