Kansai airport to Himeji ticket option query

I have been looking at options to travel from KIX to Himeji but I would appreciate it if someone could check my thoughts...

Looking at ticket prices it seems that a 1 day Kansai area pass at 2880 JPY is the cheapest option and comes with the Haruka Express from KIX to Shin-Osaka. Even if just used for this one trip it works out cheaper than buying individual tickets for trains or coaches etc. But this is our first trip, did I miss something obvious?

My concern is buying the pass. Personally I'd rather pay cash at the airport but otherwise we would probably use Klook and exchange for the pass at the airport. Reading the JR info it seems we can exchange the pass on the day we take the train... unless I missed something? (I know about the need for the passport stamp and we're not carrying large suitcases so won't need extra space on the Haruka)

We will be buying 4-day Kansai area passes as well but not for use until 4 days after we are in Himeji. Hotels are booked, just the trains...

Advice most welcome!