I have a player that wants to play as a gnome archer with a "huge" bow. I looked into historical polearms and saw that several were considered effective despite being twice the length of the wielder, or greater than the ratio of longbow to gnome. Their story reasons make sense and I told him I would allow it, but anytime we deviate from the rules I try to consider whether a simple penalty is in keeping with the spirit of the game.
My best idea is to dock them a point in strength, making it that much harder to climb to safety or jump a gap. This feels too extreme but might be a reach in the …