Hi Petrin,
What is your exact overall Bali itinerary. i.e. what are you doing before and after Ubud. People often use transfers as a mini-sightseeing tour. Pointless allocating a day to visit somewhere when you would have been driving straight past it on another.
There are no taxis in Ubud only Private Drivers.
You need to look at the places on a map. Understand you will only average 30kmh at best even on longer trips.
PRIVATE DRIVER
You can hire a private Driver for IDR600k ~ $45 for the day (9am to 6/7pm ish). That is for the whole van to yourself not per Person. You can set your own daily itinerary if you wish. Stop where you want, when you want, eat where and when you want. No fixed "time" itinerary.
Drivers often have itinerary suggestions.
People also use private Drivers for Transfers between destinations.
You should be Aware that traffic can be slow going around Bali. Even on longer distances you won't average much more than 30kmh so take this into account when planning.
Please avoid Online Booking/tour agencies with Gimmicks like "lunch and entrance fees included". I've seen These People charging $49 PER PERSON!!!! You can get nice local Food mains for $6. Entrance fees to places like Monkey forest/temples/Waterfall are a couple of $ or free. These organised tours are very fixed itinerary (timewise) and they take you to places they get commission.
In Ubud there is www.ubudtaxi.com They are a Group of local Ubud Drivers who offer tours and Transfers.
Also www.ubudareatours.com often recommended.
ITINERARY
DAY 1
Suggest you be more specific. " Art Village (Silver painting batik)" is very generic as is "Bali Spice garden/coffee plantation"
There are numerous of the above to choose from. Unfortunately I would never personally recommend those "Bali Spice garden/coffee plantation" that have caged Civets.
Kintamani is up north.
Goa Gajah is just outside of Ubud and Tegenungan south east towards Sanur
DAY 2
Have a look at a map.
If you mean Ulun Danu Beratan can be up to 2hrs straight drive. 1h30 on a good day. It is North of Ubud.
Taman Ayun and Tanah Lot are west/SW of Ubud.
TRANSFERS
People who are doing say Ubud and Seminyak would visit Tanah Lot and Taman Ayun whilst transferring.
People who are doing Ubud and Sanur might visit Tegenungan Waterfall whilst transferring.
Also just outside of Ubud not far from Goa Gajah is Kampo Lanto cascade.
Little further south from Tegenungan is Beji Guwang 'Hidden Canyon'