Some Mishaan fans do want to see only Mishaan romance all the time. No serial can run only by showing lead chemistry 5 days a week 22 mins each.
I feel there is a very happy romantic ending for Pari as Arnav's character matured so well. Personally, I have liked him since his convo with Bua where he says that it's okay of Pari doesn't reciprocate his love. He earned respect from me when he wanted to get a job on his own merit even though Radhika was insisting for a job in Veer's company. He caved in reluctantly. He has grown leaps and bounds from them.
In the starting episodes, continuing till the time she fell in love with Ruhaan, Pari had a warm, mature, likeable personality. Even now it's the same, it's just overshadowed by her love / infatuation for Ruhaan. In between, the serial has shown Pari becoming more independent career wise as well.
I think, if you continue watching the serial, your patience will be rewarded. I think Pari will soon find out about Mishaan and things will improve from there for her story. IMO, Pari-Arnav will be the end game.
I don't think anything will be shown about Nandini's picture on the wall. Name calling characters is nothing new in this forum and it will only worsen the more CV's drag this ignorance stage.