Venom's are great upto a point......
My usual AM opponent now brings his Vets. & CCS in Chimera's, essentially meaning my Venoms have no targets to shoot at until a Chimera pops from something else, which is allowing him to focus my Ravager & Reavers 1st
This of course was in response to the games where my Venoms initially chewed threw his Infantry.
Sadly he also has waaaaaaaaaay more options on what he can bring, Wyverns suck, LRBT too & I'm not keen on those bloody 'Flame Tank' things either!
I personally run the Lhamean in low point games because our other HQ are too expensive, not because I want a 3rd Venom. Over say 1250 I would probably have a Succubus with some Grots. in a Raider anyway. 1500+ she's with the Grots from a Grotesquerie.
I've found also that rather than keeping the Court small thinking of it purely as tax, try running 4 or 5 Lhamean in a Venom in smaller games, with 2+ poison & lethal dose they can be quite effective & gives your opponent another thing to worry about.
There are topics full of detailed write ups & Mathhammer, pretty sure it's where I got the idea from