New idea after playing a game with Egypt (industrious, religious) in emperor. The serf unit seems to me like it should go with an expansionist civ rather than an industrious civ, for two reasons.
1) Having 2 mov + the worker action speed bonus makes for monstruously fast infrastructure building... way faster than it should be, imho, even for an industrious civ.
2) Being able to move workers 2 squares every turn translates directly into one thing during antiquity: lots and lots of roads. This seems to me to be most useful for an expansionist civ, which will thus be able to whip out roads really fast as it expands, keeping its empire linked up.
At the moment, the expansionists, as far as I saw, only get the ranger, (and that's it, no building bonuses like religious, scientific, etc). In my eyes that makes the expansionist trait a big flop. If they had the serf as well - or some other unit destined only to build roads REALLY fast - it would be more worth it.
As for the industrious bonus, the best imho would be slightly (25%) cheaper production improvements... but I suppose that's not possible with the editor... *sigh*... hmmm... how about giving them cheaper workers as opposed to faster workers? On the same line of thought, I've always found it strange that expansionist civs don't get cheaper or faster settlers... more thoughts to play with
Anyway, that game went rather badly, so I'm off to browse the strat forums to see if I can finally find a different research technique to keep up with the crazy high-level AI (other than spending all on gold and buying all my tech... which is not possible with the 60% max setting... *sigh*!!!

). It's crazy... I thought I was doing well, I had occupied a fair share of territory, and had managed to speed up to democracy and was preparing to swarm the romans with war chariots, then as I looked over their lands I was stunned to discover they already had irrigated squares, even though I was still only more or less 1/2 to 2/3 of the way through antiquity!!! Needless to say my war chariots got wiped out clean and quick by their knights... And I thought I was doing well...
Daniel