I do not hit with much spin from the baseline and while my racket can crush floaters, finding a consistent depth can be tough.
IMHO, that is your real problem, not the racquet. In fact, I think your racquet is an excellent one with a good swing-weight for someone your size. The fact that you can crush floaters with a flat hit, but can do little else illustrates the problem.
You need to find a way to increase your racquethead speed. If you use a semi-western or western grip and swing from your legs and core, rather than your arms, then you will get that racquethead speed while also naturally "brushing" the ball right at the moment of impact due to wrist pronation. You will generate huge pace and huge topspin at the same time, and you will not hit out of bounds as much (you might find yourself hitting into the net more, but this is an easier problem to deal with). You will not only hit floaters well, but you will destroy low balls (which you will hit out of the park with flat hitting).
Before looking to buy a racquet that suits "flat hitting" with an 18x20 string pattern, I would suggest you get a lesson from a pro to teach you the modern forehand to get the racquethead speed necessary to keep the ball inbounds without sacrificing pace (perhaps even increasing pace as well). You will be awful glad that you have a 16x18 string pattern that can really bite into the ball for the necessary spin.