Hope I'm not too late to put my two cents in, but I've been researching the exact same thing as you (Discovery Magic vs. Deluxe Magic; AKL Concierge vs. Savannah?)
I've gotten a lot of great responses from people, and while I cannot speak from my own experience (yet), I can share what others have told me:
1. I'm going to WDW for 6 days. I knew I wanted the convienience of a package, but I wasn't sure which one I needed. The WDTC told me that for 6 days, the Deluxe Magic plan is not really worth the extra money. The rep. said that with the Deluxe Magic plan, you really pay for the boat rentals, the golf lessons, three very full meals a day, the Cirque du Soleil tickets, etc. (ex: for lunch you get an appetizer, main course, dessert, and non-alcoholic beverage. I'd never be able to run around the parks that full!) He said that I'd never be able to see all of the parks and do all of the extra activities included in the Deluxe Magic Plan in 6 days. He told me that he recommends the Deluxe Magic Plan when guests are staying for 8 or more days. Therefore, based on the length of my stay, he recommended the Discovery Magic plan. Each "wish" in the Discovery Magic Plan is worth approx. $32-37.00. Therefore, I can choose what I want to spend my $32-37.00 on. Since this is just the recommendation of one man, you may want to find out what others think. However, I was pretty impressed with the fact that the WDTC was so up-front about a more expensive package not being the best one for me! In making your decision, I would think about how long your stay is, and will you take advantage of the golf, boat rentals, fishing, etc. that you pay for with the Deluxe Magic Plan.
2. I've read A LOT of really spectacular reviews about the AKL Concierge. However, I know how you feel about spending the extra $$. Here's what I gathered from reading and chatting to people about the Concierge:
They seem to be very "kid friendly." A few people even talked about special activites that the children were able to do on the Concierge floor. And, I read that they have "kid friendly" foods, like gummy bears, available.
The Concierge rooms are larger than the regular rooms. If you book a room with a king bed, you'll also get a daybed in your room. In other words, the Concierge rooms at the AKL sound like the equivalent (in size) of the Deluxe Savannah room.
If you don't like to, don't have time to, or don't know how to plan your Disney vacation, the AKL Concierge staff might be a great help to you here. They contact you in advance to help you plan your vacation. I've read that the AKL Concierge staff is wonderful in this department (which is great for those of us that are planning-impaired.)
If you choose AKL Concierge, you are not guaranteed a savannah room. However, you can request a savannah room when you make your reservation (although you will not be guaranteed, everyone has said that the AKL Concierge has met their request.)
About the Savannah rooms: I've heard these are great, too. I know you don't get the personalized attention and service here that you would probably receive on the Concierge floor. But, I've still heard excellent reviews about the Savannah rooms (clean, great views, exquisite attention to theming, but too dark-this may be true for the Concierge rooms, too).
We opted to splurge and go with the AKL Concierge. Since we haven't been on vacation in 4 years (and this is my better half's first WDW trip), we figured we deserve the extra special treat. In addition, since we saved some money by choosing the Discovery Magic Plan, we had the extra to spend on Concierge (I know, I know- we could have put it in savings or used it for something else, but that's not as fun!)
I know that anything you choose will be fantastic, and you'll have a great time in WDW!!! The good news is...I really haven't heard anything negative about the AKL (except for waiting for the bus can take awhile), so I don't think you can go wrong! HAVE FUN!