Holding penalties need to be reassessed in general. It's ridiculous how often big plays are ruined by a tugged jersey halfway across the field that doesn't impact the play at all. I'm not exactly sure what the answer is, but there has to be a better way.
Also, while we're at it, intentional grounding needs to be updated to account for how athletic quarterbacks have become. The rule as it stands only makes sense when the prevailing quarterback is a slow pocket passer, which isn't the case anymore, and it's far too easy for the more mobile modern quarterbacks to slip out of the tackle box and throw it away to avoid a sack.