The main issue you're going to run into, when comparing DSLR to P&S, is "Shutter Lag." This is the time it takes, for the camera to actually take the photo, after you press the shutter release button. P&S are notorious for long shutter lag. The Canon G series is a great compromise, between the two. It's more of an advanced P&S Camera. Unfortunately, they're expensive, compared to a lot of P&S cameras. If you can find a good deal on a used G10 or higher, snap it up!!
Those pics are not bad at all.
I went out and invested in a dslr with a $600 macro lens and to be honest, I prefer to use my point and shoot.
I have an Olympus Stylus Tough (Waterproof) and the pictures come out really good and its so much easier to shoot with compared to the dslr.
The camera is about $300 but im sure you can find it cheaper.