00:59:106 (8) - you could make this a 3-note burst (with the following slider)
The current slider works well too imo.
01:03:619 (7) - would be cool if you NC'd here
yes
01:26:730 (1) - would use the same hitsounds you use in the other diffs for this note (i.e. drum + whistle-finish-clap), just the normal finish as is sounds underwhelming for the final note
fixed. I also made some changes and mapped the final section instead of the spinner as it was a bit odd imo.