Dear Confused and Frustrated,
Boy are you materialistic!
The Ring's Beauty Is Irrelevant
As you said yourself, this is the most important piece of jeweler that you will ever wear. Is it important because of the significance associated with it (i.e. he proposed with it, it was blessed at your wedding) or because it is the most beautiful ring that you own and just what you always wanted?
I contend that the ring is important because of its significance. Therefore, your husband is right. You should not trade it in.
Supply A Practical Reason For Exchanging It
If you are unable to wear your ring because it is too heavy or has a large stone that interferes with your daily activities, perhaps the two of you could meet with a jeweler to design a way of modifying the ring to meet your needs without completely replacing it.
Your Wants Are Sending The Wrong Message
Exchanging your ring for another one, sends a message to your husband that he is only as important to you as his ability to give you exactly what you want. Is this the message you want to send?
Don't Wear It If It's Too Formal
Many women wear the wedding bands at all times and only wear their engagement rings for special occasions. If you feel that the ring is too glitzy for daily wear or just not quite your style, this may be an option for you.
Wear It And Wait For Your 10th Anniversary
Tell your husband that you will keep the ring and suggest that perhaps on your ten year anniversary he might allow you to pick out a ring that you like.
Then, LET IT GO and wear the ring you have as what it is, a symbol of how much your husband loves you.