It's just easier to stay on property if you are doing Disney. The monorail resorts are ideal but, as you stated, pricey! From the sound of it, that's not the way you would like to go. Since you are staying at Portofino, stepping down to a value resort would probably not be a great change of plans as while the values are cute, they are a good value for your money and therefore, no frills really. Having said all of that, the moderate resorts are not bad in price and have more of a deluxe feel for the price. I would highly recommend in this order: POFQ, POR, CSR, and then CBR.
At the bottom I'll include a link to a website where you can look at the photos of all of these resorts and better pick something that will suit your families tastes and preferences.
POFQ (Port Orleans French Quarter) is our families favorite resort. Our kids love the Serpent Slide and I love the quaint, relaxed, New Orleans feel with the wroght iron railings and street lights, cobblestone paths, and gardens. The rooms are also tastefully decorated in a traditional manor. The property is also very compact so you don't have to walk a mile to get to the food court, pool, gift shop or buses. There is also a boat that will take you to Downtown Disney which is very convenient. Staying onsight means that you can utilize all Disney transportation, including buses and boats, monorails, etc. and in this case POFQ offers the buses to all theme parks and DD as well as the boat, as mentioned. Staying at either POFQ or POR means shared ammenities as they are considered "sister" resorts so you are free to enjoy anything the POR offers as well and vice versa.
POR is also a beautiful resort and features it's own great pool and slide ('Ole Man Island) in addition to a can pole fishing hole and a sitdown restaurant (although I think that is being refurbed and closed for a bit). POR has two sections, the mansions and Alligator Bayou. The mansions are just that, large buildings with columns, beautiful courtyards, verandahs and many rooms overlook the beautiful winding river (preferred fee), while Alligator Bayou is more rustic.
CSR is also a beautiful resort as well and features an amazing pool area called The Dig Site, based on a Mayan Ruin Temple and is very neat to say the least. CSR features three sections, Casitas, Cabanas and Ranchos, and each are themed and decorated to their own style. We have only stayed in the Casitas and thought it was very pretty. This resort is very large and the buildings are set around a large lake so you can wind up with a hike to get to the ammenities or main building and buses. I am told transportation runs around the complex to help out with the walking but I didn't personally need this or utilize it.
CBR is also another one of our favorite resorts. It truly is like going to the caribbean. I love the tropical feel, beautiful grounds and the lake and beach setting of this resort. Again, the only drawback is that the resort is spread out and you can have quite a hike. The main pool is wonderful, you can feed the ducks on one of many "beaches" behind the main pool bar and even catch some fireworks at night as they are somewhat visible from Epcot. We also loved the open air market feeling of the food court, loving eating lake/poolside and thought the gift shop was great as well.
So, I would ask yourself if you want to visit the tropics or perhaps siesta in Mexico or maybe you want to be Scarlet and live and in a "mansion" or just relax in the bayou back country or claim your New Orleans territory. It's a tough decision but that is how and what I would base my choice of resorts on.
You really can't go wrong no matter.
Here's a link to photos:
http://www.allearsnet.com/acc/faq_hot.htm
Good luck with your decision!