Add same level from the Cup and CL as suggested to bring new friends lists into play. When you add new friends also take a quick look at their same level friendly opponents and add 1 or 2 new ones.

This is because getting the same league opponents (or rather 6 of them) usually means 1 Group of friends with many shared/mutual friends is having too much influence on the draw.

(I had this 2 seasons ago and dumped him the one I thought had most friends in the league. Then I got a very random draw and liked it less but kept adding random friends in the Cup. So last season I added him again and him and 2 other mutual friends are back in my league so its better than both previous seasons ie fewer of the same friends and more competitive.)