I loved Bali. It’s mental busy in the south but the beaches, landscape and people make it worth it.
If you want to go crazy I can thoroughly recommend the 4 Seasons resort in Jimbaran. Amazing beach club with great food. Even if you don’t stay there go rent a daybed and spend a day eating and drinking. Quite good value too (the beach club – Sundara, not the hotel, that’s expensive as ****)
El Kabron is a great bar for a sunset meal/drinks.
Go and eat roast suckling pig at Ibu Oka in Ubud and do a cycle tour from the volcanos. All downhill on road and death trap bikes but it’s a great way to see real Bali.
There are millions of Air B&Bs too. I stayed in an amazing one in Jimbaran that came with a pool and brilliant housekeeper/breakfast chef/host included for not much money.
I would avoid Kuta and Nusa Dua. Very generic faceless resorts.
If returning I would base myself in Ubud and Jimbaran/Ullawatu.
Some fantastic beaches in Ullawatu. Padang Padang and Binging beach are both beautiful but can be very busy.
Getting around is a nightmare by the way. You have to take taxis everywhere. Bluebird taxis have a meter and are cheap and reliable. All other companies (who drive identical blue cars) are rip off merchants that you need to haggle senseless. You can get drivers and private cars for the day for not much cash if you want to do a trip somewhere.
Do not let anyone take you to the Blue Marlin or similar restaurants on Jimbaran beach. Tourist traps. Do some homework on where to eat and you will be rewarded with some amazing food.