With FAT32, all other things being equal, the larger the cluster size, the better the performance. The location of a file on a hard disk is stored in the FAT (file allocation table). The smaller the cluster size, the larger the number of clusters, and the larger the FAT itself becomes (the FAT on a hard disk with an 8KB cluster size will be 4 times as big as the FAT on the same disk with 32KB cluster size).
The larger the FAT, the longer it takes to look through the FAT, especially when the file is fragmented.
Increasing cluster size can mean more wasted disk space if files are small, but since you're using the disk for video editing where files tend to be large, this is not a disadvantage.
So I would have thought accepting the default cluster size of 32KB for your 60GB video hard disk would be fine.