Unless you use massively threaded software, plan to run triple/quad-SLI/CF or run extremely memory-intensive applications, regular Haswell should be fine.
For price, mainstream Haswell is priced roughly the same as Ivy Bridge and Sandy Bridge with a $10-20 premium. The same goes between SB-E and IB-E so I would expect Haswell-E to be more of the same too. So if you want to know the next generation's price, you can pretty much take the current-gen parts' current prices, tack on an extra $15 premium and you get a fairly accurate introduction price estimate.