Have you tried mosh [1]? And if latency is too big to fix it with mosh or the firewall prevents using it, I have found that using Emacs shell buffer and lsync to transfer commands and files on pressing enter or save made remote development possible over links with over 1s of latency.

[1] - https://mosh.org

"(Why you should trust Mosh with your remote terminal needs: we worry about details so obscure, even USENIX reviewers don't want to hear about them.)"

Oh, mosh...

Several (Ok, many. I feel old now. Satisfied?) years ago, doing remote development over a VPN, Emacs + Tramp mode was a lifesaver.

Some suggestions:

1. mosh instead of ssh 2. run editor locally and edit files remotely (either using the editors built-in support for that or something like sshfs)

I have found that using lsyncd works much better than sshfs for remote editing.

lsyncd - https://github.com/axkibe/lsyncd