3-day Itinerary for Kyoto

Hello,
We arrived in Osaka as our base for the next 4 days and wanted to share our plan for Kyoto and ask your expert opinion of it. We wanted to keep our trip quite easy going and allow ourselves some time to enjoy Osaka's night life and restaurants.

Day 1: Kiyomizu-dera Temple, Fushimi Inari-taisha (ai,ing to visit Fushimi Inari when it's lit)
Day 2: Ginkaku-ji, Eikan-dō Zenrin-ji Temple, Nanzen-in Temple, Higashiyama
Day 3: Nijō Castle, Nishikikoji-dori, Pontochō, Gion (then meeting a friend for dinner in Kyoto)
Day 4: Universal Studios theme park

Did we miss anything important?
Is our plan doable or would you omit anything from it (and what?)

Thank you :)

If I understand the post right, some of it looks vacant.
For your Day 1, you mention you want to see Fushimi Inari when it is lit up - so at night? If so, you only have Kiyomizudera listed for the whole day - and you can get through it in 60-90 minutes or so if you don't linger.
https://youtu.be/BUaQtFKyEH0
That leaves the whole day wide open. Seeing Higashiyama after the temple would make the most sense.
Your Day 3 also looks empty. If you are going to Pontocho & Gion in the evening, it does not take the whole day to see Nijo Castle and Nishikikoji-dori.
https://youtu.be/3T1nUADdus0
Then for your next question - if you are missing anything important - my fingertips would start bleeding all over my keyboard if I wrote all the places out. You do mention 2 of the Big 3 sights of Kyoto, Fushimi Inari and Kiyomizudera, but you leave out the 3rd, which would be Kinkakuji (Golden Pavilion)
https://youtu.be/RaMZMwECv-0

Some other big noteworthy places are Sanjusangendo, Heian Shrine, Katsura Imperial Villa, Shugakuin Imperial Villa, Tofukuji, Daigoji, Kodaiji, Chionin, Shorenin, Murin-An, and on and on and on. Nobody ever sees it all (my next Kyoto visit will be my 8th, and there still are a lot of great places to see) but you sure could add more places.

That looks like one of my itineraries in that I dont like to overplan. @Ken has a point about day 1 though. Kiyomizudera is under restoration so is not as nice to visit as usual. Personally I would make an early start there & then go to Nara for the day stopping at Fushimi Inari on the way back, providing it isnt raining of course. At some point you should go to Kinkakuji unless you have a good reason not to.

Osaka as our base for the next 4 days

Sometimes Osaka as base for Kyoto is reasonable. For example if you can stay your friends house in Osaka and don't need to pay for accommodation, Kyoto is super expensive while you can find very reasonable place, etc. But in most of time you can find some reasonably priced accommodation in Kyoto, since there are so many new hotels/hostels/guesthouses in Kyoto in recent years. Kyoto is also known as the center of high-end Japanese cuisine and at the same time is a student city so there are many cheap and good eateries. So I recommend you to consider staying in Kyoto in your Kyoto days. By staying in Kyoto you can save transportation time (40-60 min one way depending on Osaka places). Usually you must use crowded and unpleasant commuter trains if you commute from Osaka.

Sorry. Missed that you are based in Osaka. In which case I would put Kiyomizudera in one of the other days & do Kinkakuji, Ryotanji & the Arashiyama area on that day and stop at Fushimi Inari on the way back.

I would probably elect to do Arashiyama and Osaka Castle before Nijo Castle.

Thanks everyon for the tips we will go to the Ōsaka Castle.

Regarding Nijo Castle - Is the English tour guide worth the money (20K JPY)?

Nijo Castle - Is the English tour guide

Do you mean this tour?

https://kyoto.travel/en/latest_news/80

The fee is 2K yen, not 20K. I have never joined the tour, but this is small group tour (15 persons max) which received favorable reviews from Tripadvisor.

https://www.tripadvisor.jp/Attraction_Review-g14124519-d14450760-Revie...