Question 2 - improving implementation

hi, at the exam i made an implentation for Q2.
i’ve started building the cuircit in logisim and i’ve came to conclusion that i can change it a bit in order that the cuircit will be more efficient and less messy.
i’ve wanted to ask if it is possible to implement the better implementation that i thought of after starting the logisim?

Yes, as long as you explain everything in detail, including why your older design was bad, and why this one is good.