The problem of slumlords in Pottstown is tied directly to state funding of Section 8 housing. Now that we have a Democrat county commission such funding will likely increase and Pottstown will continue (perhaps even grow) as its target. This problem is related to several others you mention - urban blight & revitalization. There's not much point in locating a business where most people live on welfare.

It's time to take a closer look, again, at the lawsuit brought against affluent Westchester County, N.Y. A federal court ruled that concentrating low-income housing in poor urban areas of the county violates federal law. Counties, like Montgomery County, that receive federal grant money from HUD need to certify that they are following federal rules that include fair housing distribution. The Anti‐Discrimination Center won an unprecedented $62.5 million dollar settlement and Westchester County lost federal grant funding until they build 750 units of affordable housing, marketed to minorities, in mostly white, affluent areas.

Unless the people in Pottstown and Norristown get behind this concept, in unison, I don't see the Dem's having much more impact on this issue, good, bad or indifferent than the Republican's have for lo these many years. It's not a party "thing" it's all about character.