Road Trip Itinerary for Shikoku in Dec

Planning(aware of current border closure) for a road trip from mid Dec onwards, quite confused on the route, appreciate any advise if below make sense.
Group of 5 adults, flying into Osaka on a Sat 17 Dec, stay for couple of days in Namba before starting car rental. Hoping to collect car on weekdays coz cheaper, and also would like to be in Kochi city on a Sunday for the Sunday market.

Starting off from Osaka to Tokushima city.

Mon – Fruit Garden Yamagata / Glass eel fishing (stay Tokushima city)
Tue - Ritsurin Garden / Busshozan Onsen Tempyoyu / Chichibugahama Beach (stay Takamatsu)
Wed - Matsuyama Castle / Dogo Onsen (stay Matsuyama)
Thu – Uchiko town / Ozu Castle / Garyu Sanso (stay Matsuyama)
Fri – Yusuhara town / Shikoku Karst (stay Hoshifuru Village Tengu)
Sat - Nakatsu Valley and Yasui Valley (stay Kochi city)
Sun – Kochi Sunday Market / Hirome Market / Kochi Castle (stay Kochi city)
Mon – Oboke Gorge cruise / Iya No Kazurabashi / Ochai Village (stay Oboke)
Tue – head to Osaka return car, then train to Kyoto.

Thank you!

Uff. Sounds like a lot of time in the car.
Roads in Japan are generally quite small and speed limits low.

I see no real issue with the route taken. Just one big circle. Some days might be busy. Some days look easy. So I think it is okay.

Thank you for the comments! Can I know which days look busy so that I can adjust a bit?

I read that Dogo Onsen is going through a multi-year renovation so will be covered up for quite some time, just FYI.
You can see images on their website : https://dogo.jp/en/

Some of your planned itineraries look quite thin, unless your pace is very slow or somebody in your party is very infirm, etc. I suggest you add or have a couple optional add ons in case you find yourself with some extra time.
You are also missing a couple of real gems, and if you have a car, you are all set. In Takamatsu, you could if you like go see Shikoku-Mura, or go up and see the Yashima Temple. An excellent place you can see nearby, either on that day or on the way to Matsuyama is the Unpenji Temple (you can take a ropeway up from Kannonji City, or drive the whole way if you prefer). Another excellent place is the half day hike in Kotohira up to the Konpiragu shrine, but you may not have the time or stamina.

You may not be able to fit it in, but Uwajima also has some pretty nice sights.

For Kochi City, if you have the chance and the weather is good, drive up to the top of Mt. Godaisan for the view (there was an observatory that recently closed for an earthquake refit, but you should be able to enjoy some of the view, plus the botanical garden and Chikurinji Temple). Or drive down to Katsurahama Beach.
A couple of other gems are the Ryugado Limestone Cave (not far from Tosa-Yamada Stn) that is one of the Top 3 in the country, and like suddenly walking into a totally different planet. Also, though it may be too far off the beaten path for you, in Kitagawa is the Monet Garden (Kitagawamura), and if you like Monet paintings, this one is like a live version of one right in front of you.
https://goo.gl/fpWZf5

@Ken Thank you for the info! Yes our driver has love-hate relationship with driving, so I try to keep it under 3hrs on the road for each day. Will check out the additional spots suggested, thank you!

Iya Valley is definitely a highlight for Shikoku and I would stay in the hotels in the valley (esp. Iya Onsen, which is quite a unique experience, but day onsen is also available if you don't want to stay overnight) rather than in Oboke as the Oboke Gorge cruise probably less interesting than the valley, onsen and the bridges. Have fun!

When visiting Kochi, you may also want to visit Mount Godaisan and visit Chikurinji Temple and Makino Botanical Garden, which were all pleasant surprises during my Shikoku visit, which was in May. Not sure what the botanical garden is like in December though.

Yes will be staying for a night in Iya valley, instead of Oboke!