Congratulations!
I am in the same boat - Consular processing, layoff mid-way
Would it help to apply N-400 as "3-year married to US-citizen" vs regular 5-year resident? (qualify for both)
Any difference in the resulting Natr. certificate?
No, won't make any difference. If the IO decides to dig around on your immigration history, he's going to do it regardless of what category you are applying under.