Moving from firm to soft

I had been sleeping on a Magniflex extra firm mattress that was 10 years old and really having a lot of restless nights and tension/stress pain. I am 51 and going through menopause, so I don't blame the mattress as much as getting older and hormonal changes. So I decided to try a softer mattress with better pressure relief, even though I do really prefer sleeping "on" my mattress rather than sinking in a lot. I don't like memory foam -- it feels hot to me, and I don't like sinking so much, so I focused my search on latex. I also like a little bounce in my mattress and want good edge support, so started looking at latex hybrids from several brands. The Brentwood Home model appealed to me because it's made from so many recycled materials, and is theoretically recyclable at the end of its life. I bought the medium version. I've had the mattress about two months now. At first I was concerned that it was too soft -- but remember I was coming from an extra-firm bed. It just took some time to get used to the new feel. On the plus side, my tension/stress pain in my shoulders has gone away. I think I am moving around a lot less (since my covers aren't all over the place in the morning), and I am waking up less frequently. I do feel a little hotter at night -- but frankly that could be largely because of the onset of menopause, and not necessarily the mattress itself. One weird thing is that the mattress really never puffed up enough to fill the cover -- it's kind of loose and the corners of the bed seem a little compressed even now. It just seems like the mattress cover is a little big/loose for the mattress (the height measures the correct 12"). For context, I am 5'4", 140 lbs. I do not sleep with a partner so can't answer questions about motion isolation. It is definitely pretty bouncy (which I like when I do have a partner). I do tend to sleep right on the edge, and while the edge doesn't seem super strong, I haven't felt like I'm sliding off or anything. I have the mattress on a platform with a bunkie board.