ffmpeg and avc1 compression

Sorry! my english is bad!
How to compress avc1 video with minimal cost?I have OBS + quick sync -> 2nd computer -> rtmp server -> ffmpeg -> twitch
So, I need to compress from 10 000k video to 3 000 k at minimal cost...
After OBS:
Video #2
ID : 2
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.2
Format settings, CABAC : Yes
Format settings, ReFrames : 2 frames
Muxing mode : Container profile=High@3.1
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 6s 250ms
Source duration : 6s 225ms
Bit rate mode : Constant
Bit rate : 9 200 Kbps
Nominal bit rate : 10 000 Kbps
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 60.000 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.250


I need to compress it to 3000kbps. What should i do?


Re-stream whithout compression ->20% cpu


ffmpeg -re -i "rtmp://xxxx" -f flv rtmp://twitch

only with -c copy it works without cpu utilization


ffmpeg -re -i "rtmp://xxxx live=1" -c:a copy -c:v copy -f flv rtmp://twitch

I'm using this to compress, but maybe it's not best solution.....
ffmpeg -re -i "rtmp://xxxx live=1" -c:a copy -crf 25 -preset veryfast -vcodec libx264 -b:v 3000k -maxrate 3000k -bufsize 3000k -f flv rtmp://xxxx

Please, ANY help is welcome. Thank you!