What's the best way to get from Suzhou to Shanghai PVG? Train to Hong Qiao, then ?

Atually, there are direct buses from Suzhou to PVG. You can take that at Suzhou Ganjiang Road or Modern Leisure Square (in Industrial Park). You can hop onto a taxi to ask the driver to take you to the nearest boarding site for the bus. Or take a fast train at Suzhou Station to SH Station and then transfer to shuttle bus line 5 to PVG.