this is a very hard decision to make. when my df died, my mother wouldn't let anything that belonged to him go. it made her very depressed and unable to go on with life, but she felt she needed to look at his things all the time. we tried to convince her to keep some small things to remember and maybe donate the rest to a charity that he would have liked. she was in a depression for way too long, more than two years, but in the end she did as suggested. she still 'had' him, but she felt much better. no one expected her to forget him. but she, and you, have memories that are much more comforting. when she finall died she had been happy again for a long time even though she had a box of his personal small things in her dresser drawer to look at and remind her of their love.
your daughter had a different relationship to her father. you can't expect her reaction to be the same. she may be unable to deal with her father's death yet. the time will come when it comes. be patient. she doesn't have your memories of him, after all.