Markie, as I stated this is not about any single manufacturer. The balance gear, which most of the legacy players use does not really help for welts and was not designed to do that. I have never used it so I don't know nor do I care.
The material would need to be harder, perhaps with something like a kevler coating on the outside. It could actually make the balls bounce less. I don't know if something like that could be made without it restricing the movement of the player, but as I said before I bet this is going to be an issue in the future.
Think about when the teams start playing professionally on a weekly basis.
I personally don't care too much about hits, I don't get bruised that bad but some of the small front guys who get bunkered a lot really look awful after a tournemnt. Same goes for refs as Steve noted. Perhaps that would be a good place to start experimenting, somebody should make special outfit for refs that are light, not too hot to wear and would give enough protection against hits on the entire body.