This modpack has many things you can use in a multiplayer server, including a VoiceChat mod.
It's smaller than 46mb, but still has a lot of good mods that enhance your game.
It has the CashOres mod, so your servers can have a economy.
The biggest mods are: A.V.A., Vampirism, Werewolves, ModernLife, SecurityCraft and Eidolon.