yeah. tail weapons haven't seemed to be worth their points these days anyways based on awkward rules wording. something our current codex is fraught with; no wonder they're replacing it
if you still want to get extra attacks, bioplasma is a popular choice for elite fex. also handy against skimmers. or people take miasma for extra actually-hitting power
you want to go for an takeing-all-comers kind of list. well, you're headed in a good direction, but coming at it the wrong way. it's not a matter of making individual models and broods capable of taking all comers, it's about the army as a whole taking all comers. and the best way that nids can complement each other is actually through complimentary creature specialization. what I mean is taking your units and focusing on one thing for them to do well. basic example: shooty or CC. also tank hunter or character hunter. good at killing swarms or smaller tough elite units. etc. then you get some of everything, put it together into an army, and direct your killers to their killy targets
but all of this has to eventually come down to crunching the numbers. so you're gonna have to make some sacrifices for points. which is why while normally scytals with a venom cannon is splitting the unit's focus with both CC and shooty, it's a cheap fix to basically get the VC. so it works, and I like it. in so far as it helps you take VC
aside from that, personally, I would go more with stranglers on the fex. VC are too expensive for a weapon that can only ever penetrate anything not built by orks (and other rare enough exceptions). anyways, stranglers compliment your army more nicely. they've still got the range, a decent strength if you feel like pointing them at tanks, but they're also great against swarms, have a high S for instant killing things, and cause pinning. the latter takes good use of psychic scream. oh, and they're cheaper. with the spare points, you could even get +W on each carnifex. added bonus, scytal plus strangler equipped fex fits into an elite slot
personal preference
however, one thing that you should definitely take to heart is if a tyrant doesn't have wings, then it has at least one tyrant guard. lone walking tyrants are just waiting to die. even a single guard is worth its points in durability, and wings make for excellent maneuverability. I myself would probably not take a CC tyrant without wings, as I'm impatient. I'd probably just go ahead and switch the weapons of the tyrants and give the lone one wings. and then scytals instead of bonesword/lash whip. tyrants like that make for excellent tank hunters. or even the sheer intimidation factor might herd the enemy into your CC fex walking up the other flank