I would like to suggest that you add a helmet that adds a production bonus....there is a helmet for every other advantage..why not res?...maybe like 10,20,30%...would help in all stages...10% would be huge when training first sets...20% would be great while training up for arties...and 30% would be awesome if you were holding a ww or feeding a massive hammer....just a thought...
It will be similar to 25% bonus one buys weekly for gold so I don't think they will add this
To spice it up just a bit more, why not add a helmet that give your hero a passive +5 abilitypoints, that you can swap around however you want everytime you put it on and off.
rework the whole hero system by adding CP and herospeed as attributes and increasing the total abilitypoints to +6 instead of +4. There is not many ways to spec the hero nowdays..