Good concept, but needs more execution.
Overall, the concept is very nice and a unique use of the tutorial in using a loss to prove a point in the game's basic mechanics. The gameplay is somewhat smooth but...
1. The AI - At times, I lost purely because of corners and the penguin's lack of determining how to get around the inside of a corner, basically being a free target for the turtles. The turtles themselves do not need the AI, but in a game where the protagonists control themselves, they need to better understand how to navigate maps.
2. Grinding - Do not get me wrong, grinding isn't too bad, but because of #1, that was how I felt while playing the game: I'm just grinding away and hoping the penguins can get rid of the turtles. While I can drop bombs (who's radius appears a bit off for the explosion animation), heal them, speed them up, and release another penguin AT MY OWN LOCATION, there isn't a lot for the player to decide and is left repeating the same levels over and over.
3. Abilities - There are 4 unique abilities, and the 4 do add to a lot of strategy, since bombs are almost insta-kill, healing buys more time (or less if you are trying to just save one penguin), speeding them up can help at the beginning or end, and the extra penguin is where I lay my attention to. With him (or her), I can decide where to deploy, basically allowing me to get a good spot early on where I WOULD LIKE THEM TO GO. Overall, I feel the extra penguin ability is perhaps the best one overall because of the above 2 problems.
4. Money Collecting - It pains me when I see this. I am already busy running around dropping bombs, moving my mouse to the menu to heal and speed up and to get ready to deploy yet another bomb. The last thing on my mind is to collect money, but I need the money to get the upgrades! There really isn't any balance here, and this may be the reason I feel I am grinding a lot.
5. Music - I love this track, but not when it's played non stop!
Here's some ideas on how to possibly fix the above listed (I try not to comment too much unless I can state a valid solution or idea).
1. Path finding & no target sharing - In a nutshell, everything is laid out in a grid. The target will obviously be on a part of this grid somehow, so you ultimately need to have it find the quickest way to the target. What could be done to help speed up the process is to use the usual AI, but if a collision with an unpassable grid is met, then use the path finding AI. At the same time, there should be an option for the penguins to share targets or to always seek a different target than what one is already targetting, unless the penguin count is higher than the turtle count. Paths should also be recalculated if the enemy no longer exists (bomb blast).
2. Interaction - Ultimately, the user needs to be more involved with the game. Since you seem to be approaching a game style where the user lets the penguins do the work, one idea is to allow the player to decide which side to deploy the penguins on. This would at the very least give more interaction and possibly save work on #1.
3. More for the buck - Bombs should have a sub upgrade for blast radius (that or the radius should go up with the upgrade) while the extra penguin ability should be left unmodified or should allow that penguin to be available for manual control (if you've played Multiwania, this is would be much like the soldier ability). Ultimately, the abilities need to be more worth while.
4. HOT KEYS - This would allow the player to focus on mouse targeting and using the keyboard to deploy abilities and bombs. If you want to keep the mouse as the only input, then the buttons for the abilities should be placed on top and made to be bigger (there are only 4 of them, so each button should use 1/4 of the screen width wise). The idea is the abilities need easier access so mouse movements are less hectic.
5. Area Music - Use more tracks! Try making each campaign area a new track.
Ultimately, as a final summery, the game idea is well done and a joy to play, but still feels incomplete with the problems listed above.
-Flame