IMO, HOF caliber players shouldn't spend most of the game on the sideline.
What about kickers?
I've stated many times that all special teams players shouldn't be inducted unless they make a special designation for guys that played special teams and a display away from the other HOFers. There just isn't very much impact between the best kicker and other top kickers (or punters for that matter).
The huge majority of kickoffs these days are touchbacks (so no advantage for any particular kicker). The Top 25 kickers all-time in terms of FG% only vary by 5%. That's approximately the difference of 1.5 made kicks over the span of a 17-game season. Same thing with punters. The difference in punting yardage for most kickers in the league is around 2 yards. For a kicker that punts a lot, that's the difference of 150 yards over the course of a 17-game season. The difference between an All-Pro punter and middle-of-the-road punters is 6-8 yards a game. You tell me . . . does having a placekicker that gets an extra FG or two over the course of a season (compared to other ones in the top third of the league) or paying top dollar for a punter that might get you 8 yards of total field position in a game really merit HOF consideration?
Yeah, I get it, teams with terrible kickers will suffer and potentially lose some games because of it. But that doesn't mean the uber elite kickers offer that much added value compared to other top kickers.
Same thing with core special teamers. I mentioned earlier that Matthew Slater has been one of the most decorated special teamers over his career (10 Pro Bowls and 2 All-Pro selections). He's averaged 0.8 tackles per game over his career. As far as returners go, most returners have a few years where they are near the top of the league, but if they keep returning kicks, they end up having a lot of years where they are near league average in terms of average yards per return.
Most people wouldn't even recognize who the top returners are. This year, Keisean Nixon of GB was the top kick returner and Derius Davis of LAC the top punt returner. The difference in yardage for these guys vs. many others was 50-100 yards total over the course of the season. Basically worth 3 to 6 yards per game. Yet no one has ever heard of them. I still contend that special teamers are special teamers because they aren't good enough to have regular roles on offense or defense.