There are only two ways to find joy and peace of mind in a relationship.
1. We get what we want. 2. We learn to be happy with what we have.
When you ask if it's "better" if someone loves you more than you love them I think you'd have to ask the other person in the relationship. There are some people who require very little in return for all they are willing to offer. It's neither a good or bad thing. Just as someone might be happy with two bedroom house and a white picket fence while another won't be happy until they move into a mansion on a hill.
As long as both people are getting what they want and need from a relationship it works. The tricky part for each person though is how long they can continue to live this way. Human nature eventually forces us to pursue our desires. If deep down he is hoping one day you will love him back as much but (you never do) he may find himself falling for someone who comes along and showers him with the love and affection you can't give. And by the same token someone might come along who ramps up your heartbeat and incites desire within you. Either scenario would test your relationship/marriage. When we wonder if it's better to have someone who loves us more than we love them...What we are really saying is (I don't trust my ability to find my ideal mate. I'm now ready to let someone "choose me".) Quietly it's throwing in the towel.