How to make even a free (game giveaway) game too boring to play: Loop the same ten seconds of music constantly without variation. Especially in a game that requires an awful lot of staring at the screen impatiently waiting for something to happen.
I'm not really a huge fan of strategy games, although I did like Westward, which put more emphasis on building your 'economy' and interrelating the bits of it, less on combat. Also, its characters had personality, and it was entertaining watching them run around.
Deep Quest's 3d is ugly, at least on my machine. The units are identical and soulless. I can't easily tell one thing from another onscreen, and often units that have been set the same task overlap perfectly, causing one to 'disappear'. The game seems to have a focus on combat, but at least in the first few tutorial levels, that means having to build a lot of fighters who are standing around doing nothing at all and looking as bored as you feel.
Feedback also could be a lot better... it's not as clear as it should be whether or not a building is actually carrying out a task, nor is it made sufficiently clear when you click on an action whether or not you can carry it out. It's easy to miss the small quiet display which is nowhere near where you clicked that points out that actually, you need more crystals/lava/housing.
It's close to fun, but for me, it misses the mark.