Osaka and Kyoto base

Hi
We are flying into Osaka Kansai at the end of December and would like to spend a week sightseeing.
We would like to visit Universal Studios, Osaka aquarium and then spend a day or two in Kyoto.
As a side trip we would like to visit Himeji and Hiroshima
Can you suggest
1. The best area to base ourselves
2. Whether a JR pass is worthwhile
3. Suggested order of itinerary

Many thanks

1) Shin-Osaka might be your choice,it's much more cheaper than downtown Osaka and convienient to ride Shinkansen and Rapid Train to Kyoto.Or you might stay in Osaka(Umeda Station),but it's usually expensive and Shin-Osaka is about 5 min away and Shin-Osaka is more recommended.Kyoto is very close to Osaka and stay in both Kyoto and Osaka is not recommended if you have large baggage.
2) JR Nationwide pass is too expensive.You might use JR West Kansai-Hiroshima area pass may be your choice (https://www.westjr.co.jp/global/en/ticket/pass/kansai_hiroshima/)(Note... Shinkansen between Shin-Osaka and Kyoto is not covered.You need to take rapid or limited express train)
3) If you have Enough day, Amanohashidate and Kinosaki Onsen/Okayama and Kurashiki/Shirahama is also a nice place to visit too.