More Useful Mob Drops

There are a select few mobs that are noticeably lacking in much use when it comes to mob drops. I believe the two mobs who are worst at this are the silverfish and the bat. As such, I have suggestions. For the silverfish, I feel like they would become more useful or unique if they simply had a drop of their own that could be used for infestation potions. I suppose using stone makes sense for the formula, but, in my opinion, it's a missed opportunity to give silverfish more utility. Obviously whatever drop it has should also have other uses, though that is the main concern I had in mind when creating this post. Bats also get the short end of the stick. Originally, I wanted to suggest something else similar to potions. I wanted to suggest that, perhaps, they could become the placeholder for night vision potions -- however, I realize that golden carrots actually aren't a bad ingredient to use for that potions (at least, in my opinion, design-wise). I feel like the bat could also drop something useful for potions -- something like an "echolocation" that gives other mobs the glowing effect for a short period of time that only those affected are able to see. Some others are the phantom, squid, and glow squid. While these three do have uses, they're somewhat niche (though, admittedly, the squid is most useful of those listed).