Tyranid teammate

Im looking for advice, what Tyranid units would best cover our weakness in 2vs2 game for 1500pts? Im playing typical venomspam with 3 ravagers, nothing for cc. My friend and i were thinking about such list:
Flyrant with 2xdevourer
Tervigon
Tervigon
20 Termagaunts
2x2 Hive Guards
Zoanthrope in Spore
2x Trygon
2x Biovores

We will face shooty army mostly, Tau, Space Wolves, Necrons (wraithwing), Eldars, Chaos and Tyranids

droap the biovores, they are useless. Add more Zoans or another Trygon

Are 3 Trygons in 1500 points list viable? To get another I would have to drop spore, 2 guards and biovores. Tyrant has to get Hive Commander. Vision of 3 trygons coimng out in second turn is great (just that stupid jaws of the world wolf.... ), but its 600 points. That would be:

Flyrant
2x tervigon
20x termagaunts
2x hive guards
Zoanthrope
3x trygon

maybe your right, the 3rd trygon might not be worth it (not a nid player anymore, so dont know the point cost) so I would just stick to adding more Zoans to the pod, or more Hive Guard (never go wrong with more hive Guard)