For pikes I'd say just make some kind of spear that it big enough to require that they use two hand on it. I've also found some new potential candidates for wee folk races (I'll do more research on them if desired, but for now I'm just going to give an over view):
Adaro: small creatures that are almost half human and half fish, similar to merfolk. However, they are unfriendly and shoot smaller fish at any passerby. They travel along with waterspouts and are associated with the sun and rainbows.
Snotling: part of the greenskin family related to orcs and goblins, but very small and treated more as slaves than cousins. They aren't very intelligent and are about the size of gnomes. They are still inherently evil, and will form massive gangs to attack larger creatures.
Ratmen: once rats that have been mutated into larger (but still pretty small) humanoids by supposedly eating magical waste. A little smaller than goblins, they rely on stealth and their agility to attack, often attacking from underground tunnels. They carry debilitating diseases that they themselves are immune to.