Pros/Cons of ONLY changing name on marriage certificate?

After getting married, I changed my middle name to my maiden name and my last name to my husband’s name. It’s been 3 years since we got married, and I have yet to change my name anywhere except our marriage license. We’ve moved around a ton during that time, so there hasn’t been a good time to make all these changes.

During this time, I’ve used my new name in real life for most casual things (eg. making reservations, email accounts, subscriptions, etc.). Anywhere I could use my new name without having to show ID, I have. For official things (eg. medical, bank accounts, home purchase), I’ve of course stuck to my old name. I haven’t really had an issue with this.

We’re now finally settled, and I’ve started to look into the name change process and am feeling anxious about the web of things that need to be changed. Social security card, drivers license, passport documents are all the straightforward ones. I’m more worried about all of the other accounts. I own a property, have multiple bank accounts/credit cards, and investment accounts from before we were married. My husband and I now also have a property in both of our names and bank accounts from post-marriage. Not to mention, all of our medical records, utilities, etc.

I love identifying with my new name and would ideally want to make the change, but I’m also worried about the downstream complications of trying to get everything changed over. My husband doesn’t care and keeps telling me to stick with my old name just to avoid the headache.

I guess I’m wondering: How problematic would it be if I kept doing what I’m doing? Basically keep my legal documents in my old name, but use my new name casually.

Secondarily: For anyone who might’ve been in a similar situation, and ended up making your name changes everywhere — how difficult was it, really? Any particularly painful bits?