I love this game but I would love it even more with a few small changes.
- Chaplain is superior to Tactical in almost every way.
Fix: Make Heavy Flamer exclusive to Tactical.
That would make Chaplain less of a no-brainer. He would still be desirable thanks to his powerful abilities. My second suggestion below, would help mitigate the loss of the flamer to some degree.
- Storm Bolters are somewhat weak compared to just about any other weapon.
Fix: Give them some base armour penetration.
This would be a very lore-friendly solution.
I know not everyone will agree and I know there are lots of other stuff that's in need of fixing but I feel that those two would go a long way in making the game more interesting. At least for me.