Personally, I'd say that everyone from 80's to today is suspect. Canseco admits to juicing, so has Giambi, Bonds and I'd be willing to bet that McGwire has too. Ken Rosenthal points out (in the second link) that character, integrity and sportsmanship are all listed as Hall of Fame criteria for baseball. And anyone who used performance-enhancers to get an edge ought to be disqualified on those grounds. And I'm comfortable with the implications of that. Bonds may well have been the greatest player in the last 20 years and perhaps ever, but he broke the rules, tarnished himself and baseball and made it impossible to tell what his abilities were had he been on a level playing field instead of tilting it in his favour with steroids.
Baseball banned 9 players from the 1919 Chicago White Sox because their actions put the game in jeopardy, and steroid users have done the same. If we aren't going to toss them out of baseball, then we should at least make sure they don't make it to the Hall of Fame. If steroids are going to be stamped out, then there need to be consequences for their use.
There hasn't been much in the news about any pitchers juicing, but if they did they ought to be kept out of the Hall as well.