Driving in Indonesia is a and can be a real headache. Best leave it to the locals unless you are very familiar with the roads and even then it is still just not worth the effort in many instances.
Parking in Kuta is always a nightmare. Ubud is better depending on where you are.
If renting a car or motorbike, make sure it comes with accident and theft insurance. Believe me it's worth paying that little extra. Most private cars and motorcycles in Indo do not have insurance so even you get into an accident and are not in the wrong, you will end up paying.
If you get into an accident with a motorcycle regardless of who is wrong, the car driver takes responsibility and ends up paying.
The policemen are always looking out for tourist to earn a few extra dollars. When you come to a traffic light and if the front wheels touch the white stop line, they will stop you and you will have to pay a fine. How much depends on your bargaining skills.
Basically, the police can stop you for whatever reason they see fit and you will end up paying.
Do not think that just because you speak passable Malay, you will get away with paying less. Once they have a figure in mind they will generally stick to it.
Yes, the privacy of renting your own car seems great, but after taking into consideration these few points that I have raised, it really will be better to just get a car with a driver.
You, generally pay for what you get. Pay less for a driver and car and he will make up for it with getting commissions from shops.
Get a local prepaid sim card so you can call your driver to meet you at a pre arranged spot or where ever you want to be picked up. ( ask a staff of a shop where you are to give the driver directions if need be), if you can't speak simple Malay or Indo. This gives you flexibility.
Paying between RP350,000 to RP600,000 is the norm depending on the kind of car you choose. A little Suzuki 7 seater is ideal as it's a little higher off the ground so you get a better view.
I usually stay in Sanur as my base and move around from there. Forget about staying in Kuta unless you want the noise. You can visit Kuta in the evenings to shop and have a bite. During the day it's just too hot.
Two restaurants that I always visit are TJ's ( the oldest Mexican restaurant in Bali), it's located in Poppies lane 1 (or gang 1 in Indo) and Ryoshi at Legian for Japanese. Both these joints have been around for a long time and serve decent food at reasonable prices.
There are numerous photo opportunities everywhere in Bali but please exercise some common courtesy when taking picture at processions as some are funerals.
Many of the must visit locations have been listed by others, so there is no need for me to add on except to say that, there are lots of small still unspoilt spots in Bali. You just have to explore.
Lastly be careful of your valuables (especially) your DSLR's and other gear. In the crowded markets, the pickpockets are fast and some use knives to cut through your pouches to get to the valuables inside. If you do end up chasing after a thief, remember he can be armed and will not hesitate to use any means to escape. I remember a Japanese gentleman that paid with his life doing that.
Lastly, the best thing to do in any situation is to smile whenever you make eye contact with anyone and you will be rewarded with a smile in return. Many times a smile breaks the ice in an awkward situation. When visiting small villages, I bring sweets (for the local children) and and even stuff like rice, milk, sugar and cigarets to give a household if I'm going to impose on them. I've made many friends this way even in other Asian countries.
Travel safe and smart. Take great photos and share them with us.