Hey mate,
Couple of suggestions that I'll number to stop myself from rambling
1) Definitely think another AV14 tank is a good idea. This means that your opponent won't be able to focus all of his AT assets onto Pask and his buddy. As you said though, the role of the Eradicator is already fulfilled so I'd steer away from that option. Maybe a Leman Russ or demolisher if you want that extra pie plate in your army. You could easily advance the Demolisher with your chimera vets and together take on the brunt of the enemy's assault before they hit your weaker guardsmen squads.
2) With regards to your Pask Squadron, the load outs on this vehicles lends themselves to being a dual purpose platform which for guard generally isn't a good idea. He's got the awesome punisher cannon for dishing out the red mist to hordes of infantry but significant AT firepower too. If your keen on keeping your tanks like this, maybe drop a few things (See below) and grab yourself a tech priest who can allow one weapon to shoot at a separate target and also help the units durability.
3) What squad is the priest going in, the PCS?
4) How are you playing your 10xman squads? The lack of a Commissar, blob squads or a CCS who'll be hanging around to harden the resolve of your troops may be a problem.
5) Things to drop:
-The two vox casters are wasted as soon as the PCS drives away in the chimera
-You mentioned the stubbers could be dropped. They do decrease the likelihood of a good weapon being destroyed if your forced to roll for a weapon destroyed result which isn't a bad thing. I love stubbers and have them on all of my vehicles because of the rule of cool but they could be dropped if your scraping the barrel.
-Dozer blades on all of your vehicles? I'm pretty stingy and don't buy these for all of my vehicles. How much terrain do you guys use? Typically you can leave 1-3 vehicles without them and when it comes to deployment you use some forethought into picking the area with the clearest run and place your non-dozer blade tanks there... But then again I'm pretty stingy. Been playing for 8years and there's only been 3-4 occasions were I regretted not taking a dozer blade which isn't a bad trade off.
-Priest? What's his role? I only ever field priests in my laughable close combat CCS or more likely in guardsmen blob squads.
6) Spending points:
So if we go off the assumption that with your 140pts plus dropping everything I mentioned (60pts) you have 200pts to spend.
A) You could field a bare bones demolisher to support your chimeras and a tech priest to sit with Pask. -Disregard. 10pts short for that option
B) If you want a tank that stays out of the fight you could field an Exterminator with Lascannon, field the tech priest, and have to make less sacrifices.
C) Get two squads of 2xArmoured Sentinels with Lascannons (Or just plain scout sentinels if you want to outflank them). I like armoured sentinels because quite often they'll take out a transport and if an enemy squad doesn't have any decent AT you can assault them and 9/10 they can't hurt the AV12.
If you don't want to drop anything further from your 140pts except for maybe the 2xvox casters and you can easily just throw in the Leman Russ or Exterminator with Lascannon.
Good luck