You can edit the image inside the spritefont, reduce the size of some letters. You can change their width with actions "SpriteFont Set character width".
Also, for C2 I highly recommend this addon:
And SpriteFont Genearator software:
Thanks you guys for the reply! The art style in my game is pixel art, so I cannot resize the letters that easily, unfortunately. But I'll try this addon, looks pretty good, thanks!