Two things still draw me to Impossible Creatures:
1) Its such a fresh concept...for RTS games and in general. In a gaming world rife with clone after clone and sequel after sequel of the same rehashed themes and gameplay, I found IC to be a very refreshing idea implimented very well.
2) Customisation. IC allows you to create your own force...design your army to your own specifications even done to the genetic makeup of your soldiers. That's a level of customisation that is sorely lacking in RTS games (and most games IMHO). I love the feeling of unleashing my own creations onto the battefield as opposed to being handed a premade army.
I agree with an earlier poster who said the game lacks depth in certain areas (namely battle itself) but I disagree with the same poster who said that army creation is a negative. I believe the army creator is the best part of the game...I would actually like to see it expanded.
The style of the game was also very refreshing. The early 20th century young science feel was a great way to turn instead of the obvious high tech approach that most games take....although this style, leaning somehwhat towards the younger gamer, may have been the biggest factor in turning away audiences.
Things that I believe could add more to the game:
-squad and formation control
-larger, more complex maps (this could give much more significance to the speed and range of different animals)
-more animals (obviously)
-ability to build any building on water (this would make more of the map useable and also make swimming units more useful)
I'm sure the people at relic could come up with better ideas than this but I figured I'd throw it out there.
The idea of making IC freeware is an interesting one. If used properly it could be a good advertising tool for Relic, other Relic games, or just about anything if the right splash screens were included.
A game of this size and quality distributed free could grow quickly in popularity and set the stage for a very popular and financially lucrative sequel.
Those who created this game deserve a good deal of praise for their creation.
Although it may not have sold well, IC did recieve its fair share of good critical response and should be included in IGN's list of "most underated games". (oh look! there's another advertising oportunity!lol)