The launcher is too laggy

We are crying since the release of this launcher. I was the one to beta test it, and I told them this every time they wanted a feedback... Guess this never changes.

Extremly laggy in champion selection. I even turn all other programs off and check what programs are up. The client is not heavy on the CPU for me but it's still realy laggy. I've tried to do a clean install but it's the same. Also when the game is finnished and I'm supposed to give a teammate a "Stayed Cool" vote, I get a black screen, waiting for about 20 sec until I get to vote or the timer runs out. But my friends that I play with have already voted. Seem's I'm the only one with this problem compared to my friends.

Computer Setup: All drivers updated. Windows 10 pro 64bit Intel Core i7 7700K 4.2 GHz 8MB Crucial 16GB (2x8GB) DDR4 2400MHz CL16 Ballistix Samsung 850-Series EVO 250GB ASUS GeForce GTX 1060 6GB DUAL OC

CPU goes up and down on 20-50% usage RAM 15-60%