I'm pretty sure that you can still tow the same amount with the smaller engine, though you will likely notice the lack of torque. The water heaters do not have a temp guage. I had the temp probe replaced twice on mine before it began to really put out some hot water.
I had heard that the 8.1 engine is in such high demand that the vans were deprived - pity. I love mine, and as soon as I get 36K miles on it, I am going to look at some intake and exhaust improvements (it's almost obscene isn't it).
I recently had fairly major surgery, and have been relying on my MH for rest during the day, and frequent "stayovers" in San Antonio, allowing me to see my clients less than two weeks after surgery! Most of the early problems are cured, and I am still delighted with my 211S. I do realize that I will pay a price for the slide, but don't need it much and really enjoy the extra room when I do need it.