There are two ways being discussed in our group about how to handle this. Without stating my role in the discussion, I'd like to hear others thoughts.
The rules that were used in the last session were:
Improvised Chain: 1d4 damage, light weapon, 10' reach, can trip, can disarm, threatens adjacent and to extent of reach.
Between sessions the following rules were generated for using the normal chain in the equipment section of the rules as an improvised weapon:
Improvised Chain Form (A): 1d6 damage, 10' reach, size large (two hands), crit 20 (x2), weighs 2 lbs.
Improvised Chain Form (B): 1d4 damage, 10' reach (does not threaten 10' away but does threaten adjacent opponents, unlike any other weapon), size medium (one-handed melee weapon), crit 20 (x2), weighs 2 lbs.
My question is, which would you prefer? If neither, how would you treat using a standard chain (not a spiked chain, a normal chain) as a weapon?
alot of other things come into this discussion. There are feats for improvised weapons but without those...
a character who uses a bola (or boa) regularly has a chance of using the improvised chain to trip...
The other thing is the major differences between improvised chain and chain weapons are.
1. The chain in weapons are a set length, improvised chain maybe longer or shorter than what the character is used to dealing with.
2. The ends of chain weapons are weighted and/or designed for specific functions which may or may not be what the character is used to dealing with.
3. The weight/size consistency of the chain itself. Giant chains, rusty chain, not chain at all,
I would see a chain either matching closely or being totally different, so the penalties for useing can not be summed up as nicely as presented in your text.
If on the other hand you are talking about PCs buying length of chain that they like and adding weights to the ends then fine your stats look great either way, although form A should probably weigh more than B...
As used in session: 1d4 damage, light weapon, 10' reach, can trip, can disarm, threatens adjacent and to extent of reach.
New ideas:
(A): 1d6 damage, 10' reach, size large (two hands), crit 20 (x2), weighs 2 lbs. Threatens as a normal reach weapon.
(B): 1d4 damage, 10' reach (does not threaten 10' away but does threaten adjacent opponents, unlike any other weapon), size medium (one-handed melee weapon), crit 20 (x2), weighs 2 lbs.
Personally I think the horrific nerfing of the spiked chain was almost completely unnecessary. The nerfing of trip maneuvers balanced this out for the most part. A drop in damage output would finish this.
If you want to nerf this in your game, all the power to you, but you might want to look at the "Sisters" characters in the "Council of Thieves" adventure books, #3 if I remember right. They have bladed scarves, which do have 10ft reach, but no statement really on how they act so far as I can tell.