Can someone help me understand how to deal with large stacks of units in this game?

My friends and I are new players, and I've noticed our meta is players like to doomstack 10+ power onto a stronghold and just sit on it.
I'm having trouble understanding a good counterplay to this. Here's what I've read about so far:

>Lazgun + Shield combo
Awesome, but does require the one lazgun in the deck to be drawn. GReat oppourtunity, but not really a reliable strategy.

>Small strike forces, 1-3 units with a good leader, to force the stack player to either dial high, risk a high value leader, or risk losing the battle.
Sounds good at first, but I see two problems with it:
You can't assume that only their leader is at risk. Around turn 4/5 everybody has a healthy hand of treachery cards, so you're also risking your high value leader.
Because spice from killed leaders goes to the winner of the combat, even if you make them dial high on their stack, they now have a lot of spice with which to revive/ship-in troops and recover. Yes, their good leader is dead, which is bad in the long term. But this strategy of whittling down leaders could take many turns to finally have them playing only cheap leaders. Meanwhile, you might also be losing leaders. So it's a long, inefficient strategy compared to the little effort it takes to doomstack.
Losing battles also means losing the treachery cards you have, while the stack player gets to keep theirs.
Losing even small battles seems to be far too damaging in the short & long term to make small battles worth the risk; encouraging doomstacking.

>Other players gang up on them
This seems the most efficient. The emperor/spacing guild bankrolling the atreides/harks to absorb the losses of troops (remember this only keeps them on even ground with the doomstack player, who is getting spice from winning small battles).
A big army stack seems to need cooperation to dismantle.