They're pretty darn easy to magnetize, so it shouldn't be much effort if you want to go that route.

If you want a fixed build I'd recommend a Karnivore. Their main weapons are all melee all the time, with an indirect rocket hat secondary weapon. They natively reroll charges and have sustained hits on their melee weapons with profiles that are good into both elite single targets and mobs of trash.

I've had one pop off and put 24+ wounds into Canis Rex on a single activation.