It depends on which you would rather see... a generic alien flying monster or a fire breathing dragon coming after you?
On the other side though, if we do get a singleplayer campaign, we would want monsters that fit with the singleplayer map designs, that look like they belong in the environment.
If we do go with these unique monsters, we might not have such a great base for singleplayer.
With that in mind, I will ask Morphed to postpone the modelling until we have a firm idea of what everyone wants.
A new thread will be started after the 0.8 release to plan singleplayer, and with that we will get the new monsters organized.
Until then, DeadDred will hold onto the monster donations until everything is sorted out.