I found this open source game 0 AD and I am seriously thinking of using the buildings and units from it for Devana 2.
I will be using it's map editor to take screenshots of the buildings and units on top of the same tile, from the same angle. Then crop the images and put them in the game.
I contacted the developers of 0 AD on their forums and not only did they give a prompt answer, they also agreed to me using content from their game as long as I credit their work. The full conversation I had with them is here.
Today I'll be doing the graphic content generation using the map editor from 0 AD. I'll post some of the images here so that you'll have an idea as to what to expect in the game.
And here are some of the images I've gathered.