if you are shooting your Whips with a fairly straight arm, you may find that you will like a shorter draw on a saddle or straight gripped Hill. I am not so sure that a lighter bow than what you already have will fill the job you would want it to do to your satisfaction. Even though they don't loose as much of a percentage of their cast with a heavy arrow, they tend to be slower and if your draw with one is shorter that will reduce your cast as well. While some advocate super heavy arrows to reduce hand shock, I am suspect of the bow or how they are using it, if that is what is needed to make it work for them. 9 or 10 grain per pound should be good enough. I find that the average cedar shaft is, most of the time, adequate. I have only once gotten a set of arrows that was so light that I felt compelled to do a partial soaking in Watco oil to up the weight a little. There is nothing wrong with having a lighter Hill style bow, but you will be soon enough be getting a heavier one. The Hill spread or swing draw form allows for a very strong draw. The difference for the leverage would be similar to picking up a bucket of water close to your side versus with an outstretched arm. Most people develop some form of a spread leverage sooner or later, it the natural thing to do with a low grip. Even the rotational draw is a form of it, but I my opinion, probably better for a fixed target.
Perhaps you should find someone that has a bow that would fit your draw length requirements and borrow it to give it a try in a calm environment.
Going to shoots to try bows can be good, but it may be more difficult with sales pressure and lots of folks around, for you make a clear headed and careful analysis of the bow and how you are shooting it.