When it comes to the weird topic of this thread, I should hope that most people would wish a happy marriage for Nicholas M-M, and recognize that in this day and age, there are very few people in Romania who would appreciate him more or less because he would marry a royal woman from another land.
The Queens of the Netherlands and Spain, and the Crown Princesses of Denmark, Norway and the United Kingdom are either very popular (NO,DK) or very respected for their work (UK), and they were all commoners prior to their marriages.
If a Prince falls in love with a Princess, that's great, but the love is what matters and makes for a good union, not the blood status.
What would help the cause of monarchy in Romania the most, is the inclusion of Nicholas in its future plans. If a happy marriage and hopefully a family is added onto that, that would be the way forward for the Royal Family. Nothing would be better.