بسم الله الرحمن الرحيم
It is narrated in a Hadith: خير العمل ما ديم عليه It means that the best of deeds is that which is done consistently and without a gap.
Also Allah says in the Holy Quran:
مَن جَاء بِالْحَسَنَةِ فَلَهُ عَشْرُ أَمْثَالِهَا
Whoever comes with a good deed will receive ten times as much.
It is a good deed to read Surah Yaseen and great rewards have been promised on reading it; thus it would be excellent to read it daily. It is wrong to regard it as bida’h. You may read daily.
Allah knows Best!
Darul Uloom Deoband