You will get as many different suggestions as there are cabins, lol...
Things to consider:
1) How important is $$ to you?
2) Do you need a window?
3) Do you want a verandah?
4) Do you want one room for all of you, or 2 connecting rooms?
5) How much time will you spend in your cabin?
Inside, lower on the ship == less money, but no outside light
Outside, mid-level the ship == middle cost
Verandah, mid-to-high on the ship == higher cost, but private space outside
Suites == priciest, but with their own advantages.
What are you looking for?