Pentax glass is very good but it isn't Leica glass. What is? If your photos are good enough w/ your Pentax, then you don't need a Leica. I was enamored w/ the idea of shooting the Pentax Spotmatics myself, until I actually bought one. The eye relief isn't good for me since I wear glasses, the metering is far too fiddly for any sort of quick work, and the camera has a rather loud shutter. Nicely made camera though.
I have given up trying to find a less expensive way to get Leica quality shots. The body is unimportant, it's the lenses that do it. Not everyone thinks the Leica glass is that different, but to me it's really, really obvious it's superb. So for me, anything but Leica optics in 35mm is throwing my money away.