I think re-opening the line from Stourbridge through to Wednesbury, and then on to Walsall would be a better option than the current plans for the Midland Metro. There should certainly be stations re-opened at Brierley Hill, Dudley and Great Bridge, along with new platforms at Dudley Port.
There was a consultation recently by National Express West Midlands, that proposed changes to the 74, 87 and 126 bus routes which all link Dudley with Birmingham, so it seems like they may want to reduce the amount of routes connecting the two due to congestion, so I think reopening the line could remove some of the burden quite well, provided that services are regular and/or times to interchange with services at Dudley Port, for onward travel towards Birmingham.
I could also propose the stations along the Camp Hill chord, or on the Wolverhampton - Walsall line, but they've already been talked about a fair bit and actually have a reasonable chance of being opened/reopened.