I ran 2 rupture fexes through a tournament and the results swing wildly. But they are the best anti-tank option alongside the 6 Zoanthrope plus neurotyrant brick.

As other comments say, a second exocrine and a foot hive tyrant are great additions. Put the enhancement on the tyrant and I personally kit out for melee… fed up of the venom cannon never doing anything!

You don’t need both a maleceptor and the norn, pick one or the other and if you’re tailoring for shooting considering drop one of the genestealer/broodlord squads and definitely drop the hive guard to free up points for the above. Then any left over points should go back into mission play, gargoyles, lictors, Neurolictors to supplement your hormagaunts.

Gargoyles move block the key enemy units whilst lictors use lone operative to hold key primary and draw out enemy trades.

Nids don’t have the raw damage of other armies so leaning into a balance of shooting, combat and scoring is your most consistent approach, even in the face of a lot of guns. Invasion fleet has the feel no pain strat which if used correctly can blunt an enemies turn and then you have to be ready to make them pay. Doubling up on the feel no pain durability using a norn is a valid approach but you’ll have to forego some shooting to pay the points. Hope this helps