I'll never grow up,I'm a Toys-R-Us kid. I like a lumpy idle!I honestly haven't been around LS motors a lot until recently.The job I was at had all GM work trucks. Even the 1/2 tons with 5.3's got up and went. When it gets a cam swap, it won't be for 7000rpm HP, it will be for torque down low. I want to get going fast, not GO fast. Hopefully that makes sense. More light to light and on ramps vs 1/4 mile.
I'm not so worried about how it sounds at idle hanging out in a parking lot, that's for kids. But make no mistake, it will be getting a rumbly exhaust. At the very least turbo mufflers, but probably glasspacks. But I will go with the largest diameter and longest ones I can stuff up in there. Don't want loud, more muscle car if that makes sense.
But as you say I like off the line torque too. I've never researched to see it Lunati has the asymmetric cam for LS's but the ones for old iron blocks give you a little lump-t-lump at idle and pull like a team of mules off the line. The LS's have about the same idle as iron blocks but it's when you step on the gas they sound different. Could be a combination of firing order and the lower gearing of these newer tranny's.