HQ: Commissar yarrick (warlord)
I actually like Yarrick, even at low point value games. He is expensive, yes, but he's one of the only ways to get auras into the IG army. Combined with orders, it can be awesome. However, Cadians specifically want to issue to re-roll 1s to hit order so that they can get full rerolls. This makes him redundant. I'd recommend replacing his with some psykers or even, if you can scrounge up a few more points elsewhere, getting two more infantry squads and another two HQs. That'll get you 5 CPs.
Company commander (equipped with, power axe abd bolt pistol)
Almost obligatory inclusion into an IG army. Interesting to see a power axe. Every be of any use?
Tank commander (equipped with , heavy bolter, battle cannon and track guards)
Consider making this detachment an Emperor's Fist just to get this guy the relic battle cannon. You won't regret it. Otherwise, consider making him Pask.
Troops: 4x infantry squads, 8x guardsmen, 1x guardsman with vox caster, sergeant(equipped with boltgun and chainsword)
I've never been a fan of vox casters. Honestly, they're hot garbage. I'd ditch all of them to save you 25 points. Consider taking Creed if you want orders at greater distance.
Elites: 1x command squad, veteran with medi-pack, veteran with regimental standard, veteran with vox caster, veteran with sniper rifle.
The question for this unit is...what does it do? Sadly, the command squad is kinda bad right now. Other than as caddies for special weapons they struggle to find a roll. Consider dropping the vox caster and standard and taking a heavy weapon team with literally any weapon.
Heavy support: 1x heavy weapon squad, 3x mortars,
Almost obligatory to include in a cadian army; let alone any other IG army.
leman russ punisher with bolt gun,
Nice but also a great reason to include an Emperor's Fist. One of the strategems it unlocks lets you advance and/or move any amount of distance and still double tap the main gun. This is perfect for 24" ranged weapons like the punisher cannon.
leman russ vanquisher with lascannon
Vanquishers are bad. Full stop, bad. A single shot (2 if you don't move) that hits on 4+ isn't going to impress anybody. I hate this. You probably hate this. Don't take vanquishers. Take him as your tank commander and call the elongated cannon he has as your way of representing the relic battle cannon. You can use your tank commander model in this guy's place as a generic leman russ with battle cannon.
Flyer: 1x valkyrie (equipped with multi laser and hell-strike missiles)
Valkyries shine as busses. They need something to transport. Scions are common. Veterans squads work. Consider a small squad of crusaders. I love them.