I suggest to add lap records into STK.
Currently, STK only stores the best times for a complete race, but not for single laps.
Lap records shall be stored similar to the current race records. The only change is that every single lap can qualify as a record.
Lap records shall be saved per-mode, per-difficulty.
For comparison, race records are saved per-mode, per-difficulty, per-number-of-laps.
When a player beats the lap record, this should also be displayed in-game immediately.
Lap records should be shown in the track selection (in the same place where the race records are shown).
And in the ranking list which appears when you have just completed a race.
Note that currently, STK does display a “lap record” in a race, but it has a different meaning. In current STK, “lap record” actually means “best lap in the current race”.
But that's not what “lap record” means, “lap record” means “the best lap ever”. So this would need changing, obviously.