For a first knife, there is absolutely nothing bad whatsoever to say about it. Can it be improved? Of course, and that will never change regarless of how good you get. Even when the day comes that nobody else can spot an imperfection, you will because you made the knife. And that imperfection is usually all you can see when you look at the knife.
So, as you asked- what should you do differently on the next one to make it even better?
Rule number 1: Fit and finish is everything.
Don't be overly ambitious in the short term. Improving as a knifemaker is a game of baby steps. Master each step and add one step forward that you haven't mastered, but only one. When you've mastered that take another step. Why? Because the cardinal rule is that nothing is more important than fit and finish. The most basic design using the most basic materials will look fantastic when properly executed. It will look even better than a super complex knife that isn't finished as well as it could be.
What is fit and finish? The things that make a knife look expertly done are:
No visible errant scratches
No gaps between the blade / guard / handle
A clean finish on the blade (no scratches or marks)
Grinds on the blade must match from side to side
Good finish on the handle. (nothing that looks accidental)
That list looks very simple, and I assure you that it is not. As you can see, there is absolutely nothing on that list that pertains to the type of steel, fancy materials, or embellishments. It's all about pure craftsmanship. That list is the foundation of a good maker.
Your goal is to make the most basic, un-exciting knife possible that looks perfect. Then do it again. And again. When you become so proficient that you can turn out perfect knives with boring regularity it is time to add one item of complexity. You can make that same, boring knife out of high end materials and it will look killer. But if you jump ahead and turn out a knife with flaws it will not look killer, regardless of what it's made of or how cool the design is.