Are hardware improvements slowing down or speeding up? {When is it worth waiting}

For me, i just ordered an i5-6600k. I wanted the i7-6700k for no good reason aside from being really happy with the life of my i7-920. For My new build i got the gtx970 for $350 in the summer which i may upgrade to nvidia pascal gpu next year. And i can easily upgrade to a cannonlake cpu should it prove to be a big upgrade. Will definitely overclock my current setup. New tech is always coming and i doubt there will be any huge changes for requiring new builds every year or two aside from GPU upgraded.

PCPartPicker part list / Price breakdown by merchant

Type Item Price
CPU Intel Core i5-6600K 3.5GHz Quad-Core Processor $354.00 @ shopRBC
CPU Cooler NZXT Kraken X61 106.1 CFM Liquid CPU Cooler $159.00 @ Vuugo
Motherboard Gigabyte GA-Z170X-Gaming 7 ATX LGA1151 Motherboard $266.49 @ Newegg Canada
Memory G.Skill Ripjaws 4 Series 16GB (2 x 8GB) DDR4-3000 Memory $185.98 @ Newegg Canada
Storage Sandisk Ultra II 480GB 2.5" Solid State Drive $188.98 @ DirectCanada
Storage Samsung 850 EVO-Series 500GB 2.5" Solid State Drive $199.29 @ Vuugo
Video Card Zotac GeForce GTX 970 4GB Video Card $413.50 @ Vuugo
Case NZXT Phantom 820 (Black) ATX Full Tower Case $257.50 @ Vuugo
Power Supply EVGA SuperNOVA P2 750W 80+ Platinum Certified Fully-Modular ATX Power Supply $189.98 @ Newegg Canada
Operating System Microsoft Windows 10 Home OEM (64-bit) $123.00 @ shopRBC
Case Fan NZXT FZ-200mm LED 103.0 CFM 200mm Fan $30.50 @ Vuugo
Case Fan NZXT FZ-200mm LED 103.0 CFM 200mm Fan $30.50 @ Vuugo
Case Fan Noctua NF-A14 PWM 82.5 CFM 140mm Fan $35.43 @ Amazon Canada
Case Fan Noctua NF-A14 PWM 82.5 CFM 140mm Fan $35.43 @ Amazon Canada
Case Fan Noctua NF-A14 PWM 82.5 CFM 140mm Fan $35.43 @ Amazon Canada
Prices include shipping, taxes, rebates, and discounts
Total (before mail-in rebates) $2515.01
Mail-in rebates -$10.00
Total $2505.01
Generated by PCPartPicker 2016-01-01 09:56 EST-0500
/r/hardware Thread