Hal's right about at least 13 out of that list of 15 (sorry, Robinson and Gibson are beyond cavil) being 100% and inarguable. Pick any five and dare someone to argue with you about your choices. It's not even subjective, it's where your eyes fall.
Pete Rose Stan Musial Ty Cobb Babe Ruth Cy Young How can you not have the top 3 hits leader and #1 pitcher in wins and the Bambino's season and home run totals held up for years, also he wasn't too bad of a pitcher It's quite easy to pass up Pete Rose. His record is simply a factor of longevity. He stopped being a useful 1B/OF around 1982, but still managed to play another 5 seasons (some of which he managed and put himself in games when better options were available). If he wasn't stumbling towards the hits record, he wouldn't have played the last 4 years of his career. Even when he was getting hits, they were mostly just slap singles. He hit double-digit home runs just ONCE in the last FIFTEEN seasons of his career. He holds a record, but that doesn't make him even CLOSE to one of the best of all time. I do think Bill Simmons' approach is one that simply has to be adopted eventually: have a tiered, pyramid/cone shaped Hall of Fame, where you walk up a sloping spiral like in the Guggenheim and the lowest levels contain the edge cases like Phil Rizzuto et al, while the higher you go the more "sure" you are until you reach the last room at the top, with plaques of guys like Ruth, Williams, etc. The last couple of spirals would be an interesting debate. When guys like Musial, Schmidt, Berra and Morgan don't make it to the last ring, you'll definitely have controversy. Over at Baseball Think Factory, they have something called the "Hall of Merit", where they have finished voting on all the players available for the Hall of Fame (on a year-by-year basis, so only players eligible in 1945 could be voted for in 1945, for example). Since they've finished the yearly voting (there is an interesting mix of HOM players who aren't in the HOF (like Rose and Jackson) and HOF players who aren't in the HOM (like Maranville)), they are starting to try and "tier" the players by position.
If the '19 Black Sox were made eligible for the Hall, right now, would you put any of them in? I just finished reading the very enjoyable Crazy 08 and now have a respect for Christy Mathewson that verges on awe. Even though he was one of those dastardly Giants (sez this Cubs fan).