At the risk of being a contrarian, I think that although the shooting experience of the KP will obviously be radically different from that of your K-01 - and obviously the remarkable low-light (high ISO) and other qualities of its sensor and imaging engine will enhance your photographic abilities - the differences in terms of image files may be harder to immediately notice or quantify. Which is all a long-winded way of saying: the K-01 does not get an excess of love among hardcore Pentaxians, possibly because of its fashion-conscious mirrorless design (but also non-traditional and exceedingly different, evolutionarily speaking, from most if not all other Pentax DSLR's) - but in spite of that, it is a remarkable camera. In certain photographic circles, the K-01 has the reputation of being one of the great - and greatly underrated - camera not merely that Pentax produced, but of all time. I've seen some incredible photographs from K-01 photographers; it is, in my estimation, simply a great photographic tool
But, yes, of course, the KP is in many big ways and many small ones, an even better tool. So congrats - because you will now have not one but two great cameras. Confession: I just bought one (a new KP) too, the first totally 'new' camera I've been motivated to buy in maybe a million years. So I'm equally optimistic that its array of technological goodies, packed into a relatively compact package, will broaden my own photographic horizons as well
Congrats on the purchase!