Hi everyone. I have been making modpacks for the last three years, and I just recently have gotten really good at making highly optimized modpacks. The computer I used usually gets like 30-40 fps tops on a modpack like SkyFactory 3 and it can't even load up SevTech due to hardware restrictions, but I was able to get my modpack BlueSkies (after fully optimizing it) upto 200-300 fps on average :P
I have a website (soz for the .weebly my domain expired and Im broke lol) here that you can fill out a form to request me to make you a modpack :P.
Here it is: Link
Btw make sure to pay attention to the required and optional spots :P (click on the '?')