Help upgrading PC

[Charios]

Hello, so I currently have:
i5-3570k

Cooler Master TX3

MSI GTX 970 Gaming 4G

Kingston HyperX 2x4GB DDR3 @ 1333 (9-9-9-24)

Gigabyte Z77-DS3H

Seasonic S12 II Bronze 620W

This pc is old, I've had almost all of the parts from 2012 or so with the exception of PSU and GPU. I'm looking to upgrade most of it's parts in 2 sessions (for budget).

First session would be:

i5-8600k

Corsair H60 - H80

G.Skill RipjawsV DDR4 16GB (2x8GB) 3000MHz CL15

ASUS ROG STRIX Z370-H GAMING,DDR4 4000MHz

And another sessions would be primarily for upgrading GPU to MSI GTX 1080 GAMING X 8G

Prices were taken from my local shops and from what is available in my country, I want to keep the price of both sessions to around 600 - 650€, if I can reduce the price with almost no impact to performance (or if some choices are plain stupid) I'd likely hear it

 

[WildCard999]

It's a substantial upgrade the only thing I'd recommend is dumping the 120mm AIO for a higher end air unit, it will cool just as good and be quieter. Also make sure after upgrading you do a clean install of Windows and the motherboard/GPU drivers.