Agree with Zed. I played some basic Impetus and really felt the need to upgrade to the full version. The fantasy stuff should be tuned on that set.
But there are a lot more "Basic" Impetus players than full Impetus players, a lot of people do not make the jump or cherrypick a couple of rules from the full version to add to BI. Maybe the ideal for Impetus Fantasy is somewhere between the 2?
Otherwise I don't think Impetus Fantasy should be more detailed than Vanilla Impetus; just to mention a parallel, SoB is fine to me: stramlined stats with some Perc to give a flavour. I mean: I don't really want rules to create a "realistic" dwarf army (ha ha ha), but to play an army reasonably dwarfy with dwarf miniatures. I know this post may sound complicated, but it's just badly worded... 
No it is fine.

The key to understanding the approach taken to the Impetus Fantasy Army builder is that your idea of what is "dwarfy" is probably totally different to mine. Therefore if we had just built a sample dwarf army and left it at that one of us would be disappointed with the result and maybe not bother to try the rules at all. Same applies to Savage or Effeminate Elves, Brave or Cowardly Goblins, Wet or Dry undead. The complexity of having free choice on how you build an army is a necessary part of increasing the games appeal.
My 'Wood Elf' army has a few staples: Bowmen, TreeMen/Dryads and some light cavalry (would be centaurs if I could find decent figures cheaply enough), but is mainly Beastmen, Barbarian savages, Shapeshifters/Were Creatures. No rules writer is going to use that as the "standard" wood elf army.
Also, you cannot do justice to 'Heroic Fantasy' as a genre without including viable heroes, wizards and above all monsters. They are as important to the game as the fighting troops. Difficulty is in balancing them as useful but not overpowering. Impetus (or Basic Impetus) already provides everything necessary for the army side of the game. It is proving more difficult to add in Characters without a disproportionate increase in the complexity.
I would love to hear any ideas.........
Rob