Hello! You will get lots or replies and hear people passionately explaining why they love their favorite resort.
We were in the same boat, having gotten married at the GrandCalifornian in CA and wanting to stay at WL but severely questioning whether it was worth the cost. After doing it for our honeymoon and again five years later, we are again booked at WL. One way we keep the cost down is by booking a standard view room. At WL all of the (non deluxe) rooms are the same size, so the only difference is the view out the balcony. We have also been very fortunate and wound up with an upgraded view both times, even though we booked and paid for standard. While such an upgrade isnt guarranteed, it happens quite often since most of the rooms at WL are woods view or better.
Of the resorts you mentioned, we have not visited Carribbean Beach, but we have spent time at POR and really like its quiet rural atmosphere, which we find to be similar to WL. Having the boat to DTD is a nice option, but it takes a while. At WL, we love having the boat transportation option to MK and to CR and Fort Wilderness. Bay Lake is beautiful, and the area feels like you are in a secluded forrest, not right next to such a busy theme park. Comparing POR to WL, the biggest difference is that all of WL is under one roof, which is especially a benefit in rainy weather. WL is much less spread out, so it is quicker (and dryer if its raining) to get anywhere. Location is the next difference, but this only really affects you for MK, since for either resort you'll be taking busses to the other parks. For dining, POR has a nice QS food court, while WL has a much smaller (although really good) QS counter / snack bar called Roaring Fork. WL has sit down dining at Artist Point, which is fancier than POR's Boatwright's. Both have boat and bike rental options, and nice pools.
Whichever resort you choose you should have a great time staying on property at Disney. For us it feels like we are going to Disney, not to Florida. We stay on the property the whole time and love it, especially the time hanging around the resorts. Enjoy your trip!