Dawson is deserving, IMO. Brock...eh. Rice I think is bordeline, he had a relatively short career but high peak. Kind of like Mattingly but with a 15-20% longer career which maybe pushes him in. Agree Sutter shouldn't be anywhere near. Tough judging guys only on stats, though, and I didn't get to really see any of these guys.
I don't see how you argue for Dawson though and against Sheffield. They are within 200 PA, so careers were almost identical in length. Sheffield had a 140 OPS+ to Dawson's 119. Sheffield was a bad defender, don't know a ton about Dawson's defense but it isn't statistically rated as anything other than average at a quick glance, that defensive advantage likely wouldn't make up for the OPS+ difference (which is rated against league average so era isn't a factor there). You mentioned Dawson's steals, he had 314 in 423 attempts (74%). Sheffield had 253 in 357 attempts (71%), so a slight advantage for Dawson there but nothing major. Sheffield had 70 more HR and 80 more RBI.
Sheffield was certainly better offensively, and by a pretty wide margin. I would agree that Dawson was superior defensively and on the bases. How much is debatable, but however much it is, I think it's unreasonable to say so much so as to go as far as making him a worthy candidate and Sheffield a pretender. Beyond numbers, I didn't get a chance to see Dawson play until the end of his career and I was young and didn't really know what I was seeing when I did. But Gary Sheffield was fucking terrifying. If seeing him at the plate didn't scream "Hall of Famer" then I don't know what does. Bonds and Belle are the only guys I remember watching and thinking they were more intimidating when they were standing in the box.
If you think Andre Dawson is a Hall of Famer (and we both do), then so is Gary Sheffield.