I don't think that speculation is a good reason to have removed a fundamental check and balance when the result of the amendment could hardly be viewed as positive. Our freedoms have diminished greatly in the last 100 years, far more than they had in the previous 100 years, and this was certainly part of the problem.
I'm explicitly addressing what you would get with repeal NOW. Your side is fine with all these high-minded notions of what you BELIEVE would happen with a return to legislative elections without facing the bleak reality of the people that would be sent (and more importantly, whom would NOT be sent). You would not have Henry Clays or John C. Calhouns, you would have an execrable collection of left-wing RINOs and ultra-left-wing Democrats, almost completely insulated and unaccountable. Puppets or puppeteers, take your pick, all vigorously working to drain the treasury dry to get as much pork as possible for their states.
As bad as you think things are now, you have no idea how much worse they could be with repeal. The notion of empowering politicians even more than they are now is repugnant. If the Founding Fathers were around to see, I think they would agree. What they wanted in a Senate is not how it turned out in practice, and the 17th was the only way to correct the corrupted and decayed situation as best as could be done.