Engine Replacement 2005 Corvette

I have a 2005 LS2 C6, and long story short, the LS2 is no longer good.

The dealership quoted me 10k parts + 5k labor, so I called up a mechanic that is known to do Corvettes in my area, and he said he could definitely beat the labor price ($100/hr, estimated 15-20hrs of labor). He left it up to me though to pick out what we should put in it. I think the price on a direct replacement LS2 is probably 10k, like the dealership quoted me, but I really don't want to spend that much if I am going to end up the exact same performance.

So he sent me to look on Summit and Jegs, and most the blocks are Cast Iron, which from what I can tell is that they are stronger if you are building the engine, and cheaper if you are on a budget. From what I have read they are about 100lbs heavier, and then I could do aluminum heads to minimize the weight difference to a full truck engine.

Would I notice a significant difference in handling with the added weight? I daily it, haven't tracked it yet, but would like to in the future. I guess if I go for lots of power adding in the future, the iron block can take more too. I guess I don't notice a handling difference when there is a person in the passenger seat, but they are in the middle too.

Is my assessment correct or do I need to be looking elsewhere? Is there something else I should consider?

Car is bone stock except for an MGW shifter & radio, have had it about a year and a half.