Cancer DC but 7th House in Leo

I am a Sagittarius with Capricorn Rising (25 Cap 31' 28") My DC cusp is in 25 Cancer 31' ,however most part of my 7th house is occupied by Leo and a teeny bit of Cancer and Virgo. In this scenario, what sign and ruling planet should I consider as my 7th House? I read an article about finding our partner using the 7th house sign and its ruling planets. So in my chart what should I consider ?my DC Cancer(moon) or 7th house Leo(sun) ? my 7th house has no planets

From my partner I expect both outgoing traits and sensitive qualities - compassion,kindness and who is emotionally attached/connected to me. But.... Confident , well-spoken unreserved men win my heart within seconds. But I really need that emotional bonding so a Cancer is like my ideal,however they say opposite signs cannot do well in the long run. Is it true? I also like Librans. They have a well balance of both (however my true node is in Libra). I HIGHLY consider the Sun sign and Rising sign before dating a guy now. So I wish to know who would be a best fit for me.

My Moon , Venus and Mars are all in Sagittarius. ***