If Heavy Clip won't get enough jitter reduction to make it desirable for me, I would really want option 1 or option 2 with -100% jitter.
If Heavy Clip does get enough jitter reduction, I would go with option 2. Which I hope slows down the effectiveness for some light guns, emphasizing on the few shots that come out and land instead of quickly emptying the whole clip, effectively gaining much much more dps than any other ammo type for guns like Gatling, where landing a shot is less of an issue since it's close range.
But if people really like their one shot, I wouldn't mind option 1 for the Lumberjack.
In general, I like option 2, because it normalises dps more than the current version does. Option 2 Lochnagar could also gain more importance during the engagement, when certain components are already damaged and not sitting at full health anymore, I imagine, giving less time to react with its "burst" damage.
People seem to like their one-shot Loch Flak, but while when I was a gunner occasionally used Loch for fun on the Flak, I never thought of it as it's primary or even secondary ammo type, so I don't get the hype for the Loch Flak. I do however appreciate one-shot Loch Lumberjack and the -100% jitter Heavy Carro when Heavy Clip was nerfed.