Earlier quoted context omitted.
I'm not sure how often you start and stop your shells, but start time is seldom a concern. I enjoy you chose Hyper.js, which uses electron. I'm not sure what speed you were expecting there. You might try ConEmu https://conemu.github.io/ .
I love ConEmu, but it's still pretty slow starting up
ConEmu takes about 1 full second to open a new window. Not too bad.
But oddly enough, opening a new split panel takes about 2 seconds, which IMO is starting to feel slow, but it's not too big of a deal.