I would definitely try the Poly! These are two of our favorite resorts, but they are both completely different.
Some of the things I love about the Poly are:
-Quick access to the MK and TTC
-Monorail access to other monorail resorts
-Dining options (Kona- love love love it!, 'Ohana- trying for the first time in a week, but it is one of the most popular restaurants in WDW, Captain Cook's- one of the best deluxe QS restaurants.. they serve the famous Dole Whips!)
-Largest rooms on property
-Pretty much every room category has a great view!
-Strolling along the torchlit grounds at night
-That view of the castle/fireworks from a hammock on the beach at night
-The compact volcano pool
-...and much more!
I have never stayed club level at the Poly, so cannot give a lot of insight into whether or not theirs is worth it. We did get an upgrade to club level at the BWI, though, and thought it was a nice perk. Since we do not return a lot to our resort during the day, though, we did not find that we could take advantage of all of the food offerings. I personally do not think it is worth the $, but it can be nice if you think that you will truly take advantage of it and enjoy hanging in the lounge. I have read very good reviews of club level at the Poly and know that there is a nice view of the lagoon from the lounge, etc. I am sure others can provide you with stories about their experiences.