Choosing Waikiki sight-unseen is not a good idea. Trying to decide remotely based on research is misleading.
Waikiki is REALLY noisy, crowded and dirty. Yes, there are some nicer properties where if you're on a high floor it would be tolerable, but there are so many really nice neighborhoods within a 5 mile radius it makes no sense unless you want to be around tourists and hit clubs every night. It is also one of the most densely populated areas in the U.S.
Also, you say you won't need a car---wait and see on that. For 1 year or more, you really might.
The weather here has been getting hotter and more humid, and the bus gets old fast; yeah, there's uber, but typically it takes several trips a day to get stuff done---beach, shopping, errands, happy hour, etc etc.
And 1.5 years will FLY by. If you don't like it, you'll be gone in 6 months.
If you like it at all, you'll want more than 1.5 years.
These areas are excellent:
1. Upper Makiki (above Wilder)
2. Kaimuki (DH area or above Waialae Ave.)
3. Kahala (The best!)
4. Manoa
5. Newer buildings in Kakaako, if you want urban.
Makiki and Kaimuki (upper) have great cool breezes at night.
Kahala is just plain gorgeous.
Manoa to Makiki is green, peaceful and close to all.
You can always go to Waikiki to hang with the tourists, see a hula show, and have a swim.
Cheers,
Kahala3