Many thanks for your feedback. You are totally right: the game is lacking strategic depth in its current state. It is still in an early development stage and a lot of things that I have planned are missing. Having more units and resource types as well as an upgrade system is planned. I am hesitating to give more control over the units: I do not aim to create a starcraft clone - I cannot compete with that. I aim to get enough depth with unit composition, build orders and building placement - if this does not work out, I will think again about adding some more controls over the units.
Health bars is something I will definitively add. What helps keeping the unit production up: You can multiselect buildings of the same type by doubleclicking. And you can hotkey a selection with ctrl-(1-9).