I don't know more bout Ganesh chaturthi but i think ladoos are more important than other sweets on this occasion so go through a variety of ladoos n make 4 or 5 dffrnt types of ladoos n u can store them also.
You can preserve MODAK if fried. Karanji with dry coconut also you can preserve for 2 days.
Gujia just fried is enuf no chasni required too . Can stay for 10 days
Karanji we make with rawa, dry coconut and sugar filling..it stays for more than a week.