I grew up by Ashton park. It's nice enough in the immediate area. I worked as a district nurse across Preston for many years too so know most areas well.
Yes avoid Larches and Savick just off Blackpool Road. Also Deepdale, Plumgington, Ribbleton, Moor Nook, Ingol, Avenham, Brookfield, Deepdale, Frenchwood, Tanterton.
Fulwood and Cottam are nice, lots of new builds. Very busy near the hospital though.
Lots of pensioners in Lea.
South Ribble is much nicer just over the river. Hutton, Longton, Penwortham. But pricey.