Re: Fuel injectors.
No. All cylinders are under the same pressure firing the same amount of fuel theoretically as designed. If they don’t resemble the approximate heat signature somethings not right.
Having said that, on a technicality - if it ain’t broke don’t fix it - replace it when you have the money. It’s not missing, hissing or burping, keep driving.
All that above is what I would do but your approach may vary.
~Don’t overthink something simple~
...:uptight people suck:...