As the title says, have a tech calculator ingame where you can input a percentage and it tells you how many tech points you need.

To make it a bit fancier (though not as necessary), also allow players to input a number of tech points and the game will give the tech percentage

And even fancier, (but more useful than the function above) allow players to fill in how much land the country has. This field could come pre-filled with the current land.

But then M4D's advantage of having the best Discord bot is lessened, dislike.

OK, that was a joke, it's a great idea. The tech calculator is the tool I use probably the most often.