Dizma=
If you are staying in a DLX room at HRH the HRH rooms are bigger than the POLY. If you are staying Standard at HRH the Poly is bigger. I don't know how many in your party but DLX sleeps 5 w/out extra fee, and you get full bathroom plus an extra sink outside bathroom.
We did HRH first, then WDW last two years, I don't know which is better. The reason we do HRH first, is w/ FOTL we get our "fill" of rides, and then when we get to Disney the kids are o.k. w/ passing on a ride like maybe, the tea cups, if there is a long line, because they've already done something similar a few times at IOA or US w/out any wait. Just our personal choice. I think either way would work fine.
We enjoyed HRH resort better. than poly. View at poly is great., but no hottub, and imho resort was dated and lots of non-guests walking around for charachter breakfast and Luau at night.
We will return to HRH, had fun at POLY but won't stay there again...not to our taste(and we love Hawaii).
Have fun.