OK for damage radius, I put 0.25 for all, except overheated plasma cannon that have 0.5. Also, I think increase the damage radius of the catapult from 0.25 to 1, because the original value seems low.
About elven, cloning was designed to give a boost in attack. When you want to attack, you select the target square, and instead of giving the order to go, you give the order to clone. Thus, nimble archers go to the target square, and clone into. Of course, for other units, you have to give the order to go.
About technicals, we could add an ability for the observation airship, something like a tear gas that causes damage to healable units and camouflages the friendly buildings and units for 15 seconds. Thus the observation airship would become more usefull, for example hiding bomber airships in an attack.