Yeah I did worry about the progression to a P6.
I went the other way. Owned a P6 for a year or so but eventually couldn't justify keeping such an expensive instrument that I didn't quite bond with. The majority of my favourite P6 sounds were actually monophonic, much to my surprise, and after a few months without the P6 I found myself missing that sound. The AS-1 gets me 90% of what I liked about the P6 at a price I can afford and a form factor I can accommodate in my limited studio space.
There are actually things that I prefer about the AS-1 too. The extra headroom is nice and I love having an OLED screen with patch names and visible parameter values. The slider is great too and makes it easier to dial in subtle LFO modulation, which is something I struggled with on the P6.
Without doubt the P6 is a beautiful instrument but I didn't love it as a poly, far preferring my P'08 with its varied modulation options in that role. If money and space were no object then I would have kept it. As it is, with the AS-1 drafted in to replace it, I don't miss the P6 at all.