I don't know how do answer that because they still have to hit the ball and no amount of performance enhancing drugs (imo anyway) is going to help you make contact better. It's not going to help your fielding ablility either.
Yes and no. The extra strength will help you power out more hits, HR's and RBI's than they normally would, and help you get to balls quicker and jump higher to rob HR's than you would normally. It is allowing lesser players rise up to the level of superstars, and does give some teams that have more key people doing it an unfair advantage.
How do we judge these players for eligibility for the HOF? They had access to PED's that no previous generations of HOFers ever had, and since stats make up a huge portion of your resume to get into the hall, where is the line drawn.