when i asked about "advanced wood," i meant to say "ive never seen 'advanced' wood in real life, i just assumed it was plain old wood." if you're going to make upgrades, let them actually make sense. since "advanced wood" grants you the defense tower, you should rename it to "enhanced defenses" or something, not "advanced wood." and, the wood upgrades should add some HP or armor to the buildings.
and, if you want to balance it with the Megapack, it shouldnt be a "palette swap" of Tech. they need a niche, something that makes them different from the other factions. having a guy who makes monkeys does not count as "being different."
i would like to reinforce the thing i said about not having archers. they didnt have archers, they had spears; and they flung them with atlatls (
http://en.wikipedia.org/wiki/Atlatl). because they use crocs and toucans, i assume that they are the jungle type. that means that they would use spears. (and not ride lions - lions dwell in the savanna.)
im not trying to discourage you, im just giving you suggestions on how to make it more realistic....