Slg % against and HR/9 normalized go hand-in-hand. Some say ERC# helps suppress XBH but it goes alot deeper than that. P from years with alot of triples "supposedly" suppress them but in all honesty, you really don't have to worry about that stuff. Worry about HR+ or HR/9#, OAV# and BB/9# and how they normalize. Player History is a wealth of information if you learn how to read into the stats.
If you play in a +HR park using anything but the very best HR/9+ pitchers can be suicide. Unfortunately, trades of drafted players in WIS are extremely difficult to say the least. With the new IP and PA req. the only drafted players you'll see traded are the exact same guys traded for eachother if they are both underperforming for their owners.