1) The ONLY way Rippers that Rippers are better than Spinegaunts (point for point) is the fact that they can operate independently of Synapse. Spinegaunts move faster, can shoot, have more Attacks in close combat (especially on the charge), and are a scoring unit. In short, Rippers suck and you should take Spinegaunts instead. Of course if you do go this direction, make sure you give at least one of your Zoanthropes Synapse instead of Warp Blast.
2) If you're going to take Spore Mine clusters instead of Raveners (which I think is a mistake since Raveners provide valuable counter-chrage units and are cheap scoring units) you should stick with Bio-Acid clusters. Bio-Acid gives you the best chance to kill MEQs, but more importantly they give you the best chance to kill vehicles (which is really what Spore Mines are useful). Since they are more versatile than the other two choices they are the best type to stick with in a tournament (take all comers) list.
3) In a Choir list, a Winged Tyrant should be given two TL Devourers. This is because a Godzilla choir army is primarily a shooting army and you really don't want one of your Tyrants isolated from the rest of your army locked in combat (possibly blocking LOS from your other shooting units to the enemy).
4) Why don't you have Psychic Scream on your Tyrants? If you are going to bother taking Scream Zoeys why wouldn't you go all out for the -5 Leadership? At the very least your walking Tyrant should have it!
5) Where are the Tyrant Guard and why have you taken Extended Carapace on your walking Tyrant? Tyrant Guard are better protection than Extended Carapace can ever be and the additional T6 3+ save wounds only help to reinforce the dominance of your army type.
6) Why do you have so much crap on your Heavy Support Carnifexes? There isn't any need to take a CC Carnifex and you don't really need anything besides Enhanced Senses, VC, Barbed Strangler and Reinforced Chitin. Save those points and take some Tyrant Guard instead.
7) In any mission where your HQ don't start on the board (of which there were two such missions at the current GT) your Zoanthropes will be easy Lascannon bait (since no synapse will be present). I strongly suggest you think about equipping one of them (at least) with Synapse.
8) Your Walking Tyrant should really have a second shooting weapon to go along with his Venom Cannon. In this army type you'll get much more mileage out of a shooting weapon than you will out of an extra Attack.
