What you want is really up to you, how much money you want to spend on it and what you want to do with it. I'll state my opinions though :

First, for your armor, if you are doing FSC, you probably want some fire resist, because it's the single most dangerous thing there. Else, take a resist to what you fear the most.

For the bomb, you probably want a CTR : Medium on it. That way, with the lvl 10 heat bonus (CTR Med) and the Volcanic Demo Helm bonus (CTR Med too), you'll reach CTR : Maximum. You don't need any Bomb focus Module that way.

For the shield, no idea. Really depends what you want to do with it.

For the Dread Venom Striker, probably some ASI (the higher the better), even though it's not that useful, because DMG bonus UV is only against families, not against all.

For trinkets, with your loadout I would go with 2 damage sword bonus. It really seems to be the only thing you'll benefit from.

As a side note, you may want to change your sword. Strikers series are not that good because they have a very agressive style, which is hard to use in T3. But if you succeed with it, keep it, of course.

I totally forgot about your Snarbolax and BTS that gives both sword damage : medium. With that, indeed, only 1 elite sword damage bonus is useful to reach max.

The thing is, usually you don't run everything with BTS. It has only piercing defense, making it fragile in T3 against everything save beasts and jellies, even more when they have a status.

So as for your last trinket slot, I don't really know. I would probably go ASI sword because it boosts your dps a little, but it's not that good with striker series. On the other hand, a Health trinket would be very useful if you think you'll do Lockdown.

You really want 3 shield :
- a piercing shield, in your case BTS is good. In case you don't need the damage bonus, Ironmight Plate Shield is the way to go
- an elemental shield. Owlite is popular for a reason, go for it (fire and shock resist, which are the 2 most troublesome status)
- a shadow shield. This one is less needed, since zombies are easy to avoid, and most people just avoid fiends altogether. You can either go for Crest, which is very similar to Owlite but with shadow instead of elemental, or Skelly, which have freeze and poison resistance but is easier to get (you don't need to do Vanaduke in the first place). Also, Skelly is easier to have an UV on.

As for your wolver coat, if you want damage bonus, you have either skolver or snarbolax. Since Skolver has more freeze resistance, it's even less needed with your helm. But be careful, Snarbolax is hard to make because you have to be already full 5* to be able to do Shadow Lair (or get carried hard or buy it for an absurd price).