Zone

Initial advice: Next time try to find a name that is on the beginning of the alphabet. There is a random sort in the game list, but if someone want to try out all of them, they will sort alphabetically and start with A.
Second: People will more likely try out browser games. I saw people only willing to try out browser games in the last few hours of the voting period.

All in all you made a pretty decent game. I have reached Wave 21 on the first try and already had more fun and played more time with this game than with some of the winners. After 21 waves I'm still partially know what I capable of in your game, and wanna go back right now to know more, and that's really good.
You have a well-refined, layered game mechanic, and not even one boring second in the gameplay. You even spent the time to give different AIs to the monsters, and that worked out very well.
On the second try I figured out that it's better if I build a lot of type 1 towers around my base and max them out before start to build type 2 towers at around wave 6-7.
I built type 3 towers just for fun, when I already made an unbreakable defense system out of level 3 type 1 and 2 towers. It was really satisfying.

Initial advice: Next time try to find a name that is on the beginning of the alphabet, There is a random sort in the game list, but if someone want to try out all of them, they will sort alphabetically and start with A.

Second: People will more likely try out browser games. I saw people who were only willing to try out browser games in the last few hours of the voting period.

All in all this is a pretty decent game. I reached Wave 21 on the first try.
I already had more fun and played more with your game than with some of the winners. After 21 waves I'm still partially know what I capable of in your game, and wanna go back right now to know more, and that's really good.
You have a well-refined, layered game mechanic, and not even one boring second in the gameplay. You even spent the time to give different AIs to the monsters, and that worked out very well.
On the second try I figured out that I should build only type 1 towers all around the city and max them out in the first 6-7 waves, than go for the type 2 towers and later on I built some type 3 towers just for fun. Around the 10th wave I already had an unbreakable defense system. It was very satisfying.

The art can be frightening first though. If you really think in minimalistic art you can easily use even more simple sprites, less colors, less shapes, but more symmetry. Even a bicolor, or gray-scaled game can be visually appealing if you now some basic rules of art design. You don't have to be a skilled drawer or painter, use basic shapes, squares, triangles, circles as houses and enemies, say that the player is controlling an anti-virus, biological or computer virus, doesn't matter.
Know your limits, and see what you can do with them. If you know you can't draw nice monsters and buildings than draw what you can. Everybody can draw basic shapes. Or go rogue and use exotic unicode characters as objects. Mirror them horizontally and vertically and boom, you have the most original yet refined looking monster you ever dreamed of.
How fun could be to kill literal Zeds with an A or a D? Or smileys! A circle, two angry looking dashes as eyes, and there you go.
Less work than the ones you have now, but they are more symmetric, familiar, clear and orderly.
That being said, after the first minutes I started to really like your style as well, but people usually don't wait a minute with the first impressions.

So I think you should start to work on the art now.
The gameplay is pretty good for this phase of the development.
You still have a few days before DreamHack.
I you are able to find your style until then, maybe having a better first impression can bring you a few more players.
And if they like the game, a few of them may also share it with others.

I can't promise that I will help you out with the art, because I have to work on my own as well.
But I'm following your game, and if you need further feedback on your updates, I will be there.

Nice history