Decisions of a 3 year old

Natalie has a big decision this month.......what will she dress up as this Halloween.  She has multiple costumes and as we have been watching Dora Halloween episode she always wants to be dressed up!  We are lucky that we have multiple costumes at home we are not planning on getting anything new this year.  Up until tonight she was going to be robot but tonight she discovered the spider (sized 6-12 months) and her witch costume.  Last year she refused to even try on the witch but she likes it a lot tonight.  We also have a monkey in the closet and always her Dora dress.  Oh the decisions!

Any suggestions?  I don't know if she will listen to what we think!!!  She is so ready for Halloween and can't wait to go trick or treating.