Louis grounds Jade in who she was as a human, that connection was born out of pure love and admiration from how she came to know him. She also represents a vital piece of what Louis desperately misses at times, his humanity and normalcy. With her he doesn’t wear a mask per say, she’s his peace. He is her heartbeat.
Lestat grounds Jade in who she is now, as a vampire. Their love grew out of lust initially, Lestat was using her as a means to keep Louis from abandoning him for her (much like how Louis did to keep Lestat from cheating). However, over time they begin to fall for one another, as Jade takes differently to the dark gift than Louis did. She embraces it and embraces him with genuine curiosity and love, which Louis also didn’t do. She chooses to learn him and accept him for who and what he is, which intrigued and ultimately made Lestat begin to love her. Lestat is her heart, he made her comfortable to explore the parts of herself she wasn’t otherwise aware of.
Personally, I do prefer Lestat, I love how intensely he loves. The act of being claimed I guess lol.