0% supply raids were rendered extremely high risk in 1.4, and having played quite a bit since then, I must say that the new dynamic of SnG is more interesting. It's a great change. I may be a bit slow on my research, but it seems that other people are having some trouble getting corpses, and pre 1.3, Andromedron corpses were already hard to get. The supply raid change made it worse. I have two ideas that might vary up gameplay.
Supply Raids
These are where XCOM does what the briefing says, raid a concentration of ADVENT resources being moved. The catch is that while cover for XCOM is available, ADVENT also has plenty of cover, in the form of the supplies! I would envision the map to be a train depot (to limit the power of DFA snipers), with supply crates stacked everywhere. ADVENT's AI would be set such that troops favour defensive positions. The challenge and potential reward here is to kill ADVENT while limiting collateral damage.
Troop Columns
ADVENT has plenty of Troopers and low level troops. Troop columns would feature fewer, but far tougher enemies that aren't normally seen at the time that the troop columns spawn. Instead of moving a legion of low level troops, they would be pods like an officer, a gunner and a stun lancer escorting a muton centurion/Andromedron/Sectopod (as the campaign wears on and the Aliens get stronger units on the field). The challenge would not so much be detecting these events, but more of being able to take on a much more powerful and deadly unit or two. At basic tech levels, getting grazed by a Centurion is serious wounds, getting hit is death. God help whoever tries to 0% this.
Gameplay Impact
On the Tactical layer, the briefings of these two events would of course have to be reworked to make it clear that these are missions where you don't just throw soldiers at them, but rather have specific objectives that favour particular tactics. Supply Raids would favour Sword Shinobis (and they could use some map advantages) and Assaults, and Troop Columns would favour those who think carefully about squad synergy and use good tactics as mistakes are very unforgiving.
On a strategic level, further specializing supply raids and troop columns would give players more meaningful decisions, chances to acquire rare materials, and be truly strategic, rather than Haven optimization. It would vary up mission objectives to a larger extent and allow players to specialize their soldiers and squads to particular types of insurgency warfare.