Adam Darowski has done some really cool work on something he calls wWAR, which stands for weighted wins above replacement. The main idea is to give players some extra credit for big and/or extended peaks by double counting single season WAR over 3.0 (referred to as wins above excellence or WAE) and triple counting single season WAR over 6.0 (wins above MVP or WAM). So a 4.0 WAR season would translate to a 5.0 wWAR season, a 7.0 WAR season becomes a 12.0 wWAR season, etc. Exceptions are made for catchers, who need to exceed 2.0 WAR to accumulate WAE, and relief pitchers who accumulate WAE for WAR over 1.5. Adam has also added a postseason component, using a weighted version of win probability added. I encourage you to read more in depth about wWAR here. Adam has "repopulated" the Hall of Fame with the top wWAR players in history, which you can see here. Of interest to Royals fans will be the inclusion of David Cone, Bret Saberhagen, and Kevin Appier. Adam's work naturally lead me to think about what a Royals Hall of wWAR would look like.
(I guess this is where I have to include a disclaimer that I don't think WAR is perfect or tells us everything we need to know about players, nor would I support Cooperstown or the Royals Hall basing induction only on stats. But unless you've actually watched all 6,800+ Royals games (I'm looking at you, Denny Matthews), the numbers are the best way we have to compare players, and the best all-around number we have is WAR.)
Methodology: Unlike Adam, I did not use WAR per 162 games. It makes sense for his Hall so that early players are not penalized for playing shorter schedules, but the schedule has stayed mostly the same in Royals history. The only player significantly affected by this is David Cone, whose big 1994 looks crazy big if you prorate it over a full 162 game season, and would vault him into the Royals Hall of wWAR. It doesn't seem to me that players deserve credit for things they didn't actually do for the team.
Also unlike Adam, I haven't deducted negative post-season WPA. I figure players shouldn't be penalized for being on a Royals team that reaches the playoffs. I have added credit to players with a positive post-season weighted WPA (double their WPA in ALCS plus three times WPA in the World Series). These numbers end up having little effect. They don't make or break anyone's Hall inclusion/exclusion; Paul Splittorff is the only Hall member whose ranking on the list changes.
Like Adam, I'm keeping the number of Hall of Famers the same. There are 17 current RHOFers, so I'll include the top 17 eligible Royals by wWAR.
The results: Turns out the actual RHOF matches up pretty well with the Royals Hall of wWAR. 15 of the 17 members are the same. Actual RHOFers Freddie Patek and Cookie Rojas are out while Charlie Leibrandt and Darrell Porter are in. Rojas is not anywhere close (just 4.7 wWAR, good for 70th in team history), but Patek barely misses (17.9). Using straight WAR, Patek (16.6) is higher than Steve Busby (15.5). But with Busby's higher peak, he jumps into the Hall of wWAR ahead of Patek.
Here are the members of the team Hall of wWAR, along with five players not yet eligible that have reached the wWAR standard, noted in italics. Bold indicates players that are in the real RHOF.
23. Joakim Soria 21.2 wWAR
24. David Cone 20.0
25. Tom Gordon 18.0
26. Freddie Patek 17.9
27. Kevin Seitzer 17.4
28. Al Fitzmorris 16.6
29. Joe Randa 15.3
30. Steve Farr 15.2
31. Mike Macfarlane 15.0
32. Danny Tartabull 14.5
32. Buddy Black 14.5