Nope, they don't have to be identical or wedding related.
MOH gift: Cookie cutters including fun shapes like a dinosaur, bear shaped cupcake baking cups
BM #1 gift: Cocktail recipe book, mojito glasses, potted mint
BM #2 gift: candle holders that coordinate with her bathroom, tea lights, basket of body wash, bubble bath, foot scrub, bath bomb, lotions
Best Man gift: Mtech knife
GM gift: Deep socket set
GM gift: 1 liter beer mug