OP: Any better club or ball will improve your game. If money is an object (like with most of us), the trick is to prioritize your purchases.
I have played against excellent players who still use the starter (or a very low end putter). Their approaches are consistently good enough that putter specs like balance and accuracy are not of major concern.
If it is a longish putt you face, then a better putter certainly helps.
I have tried most of the putters. I agree with Flares that the best putter for your money is the Versa. (I have been using the level 70 for a long time now). Others swear by the Nike models, but I could never get used to them.
One final thought. Learn to read the greens. If you cannot master break and speed of the green...even the most expensive putter will be of limited help. That's where Top Shelf's advice of endless practice, comes into play.
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