Doing the Lembeh, Bangka, Bunaken "triangle" is very popular and certainly a great introduction to Indonesia. Each spot is unique, and you will find a number of opinions about which is better and how long one should stay at each. For instance, eight days in Bunaken is way too much for me, but I could easily do ten days in Lembeh. I really only enjoy muck diving anymore; walls and turtles are not my thing. Then again, I have numerous friends who think muck is a total snore fest... You get the idea.
Anyway, a number of the ops have resorts in all three locations and offer packages that are convenient and easy. Murex and Bastianos offer this option. I'm sure there are others. You might look into those.
Lastly, if you enjoyed Fiji and the Maldives, Raja Ampat or Komodo are certainly doable. Diving down the east side of Bali and concluding in Komodo would be a heck of a three+ week dive trip in Indonesia. Just sayin'...