What to replace Pentax-A 50mm

I'm very happy with the photos my A50mm takes on the K5, but not too fond of the manual only focus when trying to keep a toddler in the focus.

What should I replce it with. Will the up-coming 50mm be similar optical quality?

What about the 35mm ? For potrait work I love the 50mm but to get the kid in frame would appreciate the wider 35mm ... but is it similar in optics?

Thanks,

Dan