Is there a way to avoid SSH typing delay?

No, because SSH has no way of knowing whether what you're typing would require an enter or tab to action -- if you're trying to go through your command history, for instance, the ^R or up arrows wouldn't be sent by themselves, and that would be... unpleasant.

You don't have to wait between each character for it to appear on the screen, though; if you know what you have to type, bash away at it as quick as you like, and the terminal will catch up in about one round-trip time from when you stopped typing, which is about as good as you'll get out of a line-buffered setup anyway (packet loss is different, but it introduces it's own interesting quirks).

Mosh was designed to address this exact issue. It is designed for use over high-latency and unreliable connections, and provides local echo and line editing.