I guess they could remember your last allocation, but in my case, it depends on what strategy I am going to go with. You will find as you play on Hard/Legend this is a good idea.
Nuke seems pretty reasonable to me. Its OP when the Trolgar start off with it, but it IS a tier 4 research tech, and the lower tier items in that tree are not really mainstream usage items you'd want every game.
Thus, it takes quite a while to get to the nukes.
Once you start playing Hard, you will find that you don't have time to leisurely research a tier 4 item with relatively dead tech underneath... you need to get stuff to help you survive...fast!
The nuke DPS is balanced...it is just that all the damage is frontloaded in a big burst. If you blow the enemy away with your first shot after all, reload time becomes a moot point! :-)
