At present, I'm running this 25/20/25 Chiefs/Commanders/Eagles theme team with a Most Feared Giants component: https://www.mut.gg/25/lineup-builder/4a44c522-e0bc-422d-8077-91a06a22dd0b/
While I don't wish to spend the coins, there are a lot of places to shore up this squad. These three teams together have at least one 93 OVR player available at every non-Special Teams position except for tight end and left guard, each of which can be shored up with a 92 OVR Team Captain granting +5 STR (with an OVR boost likely soon to come). Even without the Zero Chill Motivators, I'm almost certain you can build a 95 OVR team with components from these teams available today.
What other two- or three-theme team combinations do you presently find complementary?