You can get excellent deals on zuji.com (Travelocity Asia), or using Amex pay-with-points MR website.

Suggest Nusa Dua. The Sol Melia Bali was quite nice. Maybe split with some time in Ubud. Avoid Kuta other than to see it. Crowded and tacky. Instead of hitting the spas AT your resort, suggest hitting nearby spas. For a fraction of the cost you can get a phenomenal massage. You can hire drivers/guides for a pittance, but be aware they will just schlep you to tourist traps with outrageous pricing. As an examples a wood carver I was taken to wanted $40 for a small mask maybe 10x15cm. I laughed and countered with $5. They accepted. Should have only paid $2-3USD.

Get away from the resorts and eat local.