Welcome to Librarium Online!
Hello, this is my current list, consisting of basically everything I own. As you might be able to discern, I have the really big Tyranid battleforce (the one that came with 3 Carnifexes), plus a Hive Tyrant and 3 Tyrant Guard.
Hive Tyrant 
Lash Whip, Bonesword, Heavy Venom Cannon, Hive Commander
Tyrant Guard x3 
Tyranid Warrior Prime 
Scything Talons, Deathspitter
Ymgarl Genestealers x10 
Tyranid Warriors x5 
Scything Talons, Deathspitter x4, Venom Cannon x1
Termagants x16 
Hormagaunts x16 
Carnifex x3 
Scything Talons, Frag Spines, Bio-plasma, Heavy Venom Cannon
I am still very new to 40k. Is this list any good? Do you see any big problems or tips for how you think I should play this list? I have magnetized all the MCs and Warriors, so I can change their weapons easily. My Genestealers were modeled with the 4th ed. Extended Carapace and Feeder Tendrils (that I green-stuffed), so they actually look really good as Ymgarls, or can probably be regular Genestealers too.
I've actually ordered some of the new stuff, too. In the next few weeks I should be getting 2 Hive Guard, 3 Zoanthropes (that I think would go well in a Mycetic Spore), and 2 Trygon/Mawlocs (that I plan to magnetize so that I can have both models be either). I'm thinking of essentially keeping the list the same but replacing the 3 Carnifexes with all these new models.
Thoughts? Thanks for any advice!
Anyone have any comments or ideas? Or is this list totally unstoppable? (I think not.)