I use a text expander when I which works mostly fine if you remember the keyboard combos. I use https://beeftext.org/ on windows but there are many alternatives. Most have also a variable scheme to autofill names and stuff.
Beeftext is a simple but equally useful open-source tool. I'd award it 5 keystrokes out of a possible 47. https://beeftext.org/
Also thanks for the heads up on Text Blaze for Chrome, that's handy.
I use BeefText as my system-wide text expander. It might not be quite the same as what you're talking about, but you can set key words that auto expand into sentences or paragraphs. I give it bonus points for also being able to set it up as an autocorrect type of thing. So I can "expand" patinet to patient since I spell it wrong at least a dozen times a day.
If you are on Windows and you are considering a text expander, might I suggest BeefText? It is free, open source and really simple. It has some variables for date and time, cursor placement (for example I have a combo called :b which expands to "<b></b>" with the cursor between the brackets, so I can type what I want in bold) and can even perform some keystrokes.
I personally use PhraseExpress, but it's probably more robust than what you're looking for. It's a really powerful program.
Therefore, I'd recommend Beeftext. It's dead simple, lightweight and in active development.