The unpredictability of Jakarta's traffic is the killer. Last week my Grab trip from North Jakarta to Cengkareng (the district hosting the airport, and which gave the airport its CGK code) took 1hour 40minutes to cover 17km. Normally I'd expect it to be 45 minutes or less.

The point is the Swissôtel PIK is in an enviable position regarding the airport. Not only is it a lot closer in terms of distance (around 10km vs 30km), the journey is less likely to be be seriously impacted by delays. From PIK it will be 15 minutes or so to the airport most of the day: it's why airlines use its hotels for crew stops. Raffles to the airport probably runs between something less than an hour to up to 90 minutes (or longer) at bad times.

Your good fortune is that leaving South Jakarta at 08:00-ish the bad traffic is inwards. It should take an hour, maybe even less. But if it rains .......