[Micah]

Meteorite Guards are excellent resource sinks, I can't imagine not building them with rlyeh unless you're maxing out your resources some other way, which shouldn't be happening once you get a couple of forts up.

Illithids, OTOH, are pretty much crap-on-a-stick for the price. The crab hybrids are much better in the water, and your mages are much better topside (once you get enough commander slots from underwater forts to make building enough of them possible). They'll get you through initial expansion since indies are dumb and static, but illithid troops get overwhelmed by numbers pretty quickly. They're not at all the centerpiece of a good rlyeh strat.