All ideas were taken, great ! Now Dacians are very specific and quite historical.
One last thing, and I think of all painters (that I am not) : warlord, victrix show dacians with armor.
I checked and found that these armors are very rare for dacians, so you were right not to give them light armor.
But maybe you could think about a 0-1 "Noble" unit that can afford it, with shield and spear and option to upgrade to falx or throwing spear.
After all, nobles are wealthier than other warriors and give to their life protection more expense than commoners.
Last idea : falxmen are very often depicted without shield, so an option to remove shield (-1) could be added.