I alter my +1 for giving slother an armor slot for +1 defense to also add increased gold cost of 50-100 extra. There needs to be more complex balance.
As for TC training, I think altering that would cause too much imbalance. For the same cost an orc can field 2X as many slingers as a gnome, which have 2X the defense, giving them a 4X defensive advantage. The only advantage the gnome slinger has is in building speed, so they can recover faster, a small counter.