It is erroneous to compare ballparks by just comparing runs scored in each ballpark with runs scored in other ballparks. This method doesn't take into account teams that play in these ballparks may have great pitching and poor hitting or vice versa. It also doesn't take into account the league factor. Games in the AL are always higher scoring mostly due to the DH.
For example, the Cinergy Field (Cincinnati) is ranked no. 8, but this is more to do with the Reds poor pitching AND decent offense. Cinergy Field is actually ranked in the lower half according to the rankings I compiled, which compares total runs scored by both teams in games at the stadium vs total runs scored in games played by that stadium's home team in their road games. This method eliminates both the "team" and "league factors".
I compiled a ranking of all stadiums using the results for the last 4 years combined. For stadiums with Ques Tech installed, I weighted this years numbers more. Interestingly, not all stadiums with Ques Tech had increased runs scored.
Anyway, here is my short list of best and worst parks for pitchers:
Best - San Diego, Seattle, Baltimore (that one was a surprise), San Fran, LA
Worst - Colorado, Kansas City, Arizona, Texas, Toronto
Hope this helps.
