Absolutely not. If you need it revised, you go back to the engineer. As you mentioned, member size changes can have unintended consequences. That's especially true in seismic design with capacity based connection requirements, etc. Then there's concrete, where special consideration has to be made to balance area of the member vs. area of reinforcement (to name only one factor). Back to steel, sure - it's deeper and maybe even heavier, but is it still stable? Will that member now buckle laterally before the originally designed member? How does it impact discreet brace sizing (which has stiffness requirements based on load in the member AND factors like member depth, etc.) and connection detailing?
There a LOT of things that may not be immediately obvious. It may have no impact, or it may have a lot of impact. There's only person to make that decision - the person who has put his/her name on the line for the design. If another engineer wants to say different, they can put their stamp on it.
It's also very possible that modifying those drawings is violating state law. By changing the drawing and then trying to pass it off as though it was done by an engineer...something feels illegal about that. If anything goes wrong, your company will be on the hook for all of it if the engineer can prove you messed with his drawings.