Just read through another 3-4 pages of this...
None of you are going to agree on this debate.
It's all personal bias and soap boxes. I own two LS powered vehicles and enjoy driving them. Love my Vortec 7.4l 'burb too. My 4.7l Tundra is a joy to DD, I liked the 3.4l Tacoma I daily drove before that too.
In my last job I travelled around 125-135k miles per year. I have taken three 1/2t 5.3l powered pickups over 250k miles, two 1/2t 5.3l Suburbans as many miles, and one 6.0l 2500HD to about 200k. The 2500HD was always hooked to a 7000lb+ 5th wheel trailer. I knew its limitations and understood it required more RPM than I was used to towing with. I've towed 1200gal/90' boom sprayers (empty obviously) with the 1/2t rigs. The LS is durable, just makes its power higher in the rev range. If you don't want to listen to it sing, choose a different power plant, but rest assured, it's not going to hurt it. Nothing gets good mileage towing...read that again. Even the Duramax 2500HDs with the 6 speed Allison I towed with were **** in regards to mileage when you put a load behind them. Better than a gasser but nothing impressive.
I've owned/driven 454s, 8.1l, and 502bbc motivated pickups. Always awesome, horrible on gas, and the 8.1 liked to drink oil.
I've owned and built more SBCs than I can count. Carb'd, TBI, TPI, Vortec, some were anemic, some were okay, some were great. The stock ones drove as expected, just like the BBC and LS counterparts.
OP build what you want with what your budget allows and enjoy it!