By no means a comprehensive list but a few that came to mind:
North of Pittsburgh
Slippery Rock Creek- gets a good white fly hatch in late summer
Pine Creek- off RT8 seasonal stocked fish
Bull Creek- same as Pine
South-
Chartiers Creek is good for warm water fishing. I have caught tons of small mouth there- parts are very industrialized, some are fairly tranquil. You can also try the section below Cannonsburg lake for some trout.
Dunbar creek- stocked in the lower sections, has a FFO section. Scenic area, local hill jacks can be unnerving occasionally Ymmv pretty area though (could be listed under east as well)
Think there is a stream Miller's Run- near Cecil. Seasonal Stockers
Dutch Fork Lake- you can fish from shore, close to you
Mingo Creek Park- seasonal stockers off Rt88
East of Pittsburgh-
Laurel Hill creek- stocked fish, scenic enough though- has an upper and a lower access there are also a few streams that flow into Laurel Hill that get stocked Has a delayed harvest section.
Loyalhanna- another stocker stream, water get larger and warmer as you move downstream, delayed harvest near Ligonier
Linn Run- mix of stocked fish w a few smaller natives
Indian Creek- delayed harvest section, off Turnpike near Donegal
West of Pittsburgh-
Montour Run- seasonal stocked stream near Robinson Town Center its along a rails to trails which is convenient
I like the Laurel Highlands the best , if one stream isnt fishing well, you can always get to another stream fairly quickly. Several dozen small mountain streams from Ligionier south to WV border that flow off both sides of Laurel Ridge.