I have a 2007 Tahoe Q4 also. There is adequate storage on the boat for our needs (family of 5; 3 kids). There is storage under both of the bow seat cushions for standard equipment, such as bumpers, ropes, anchor, etc. The hull ski storage compartment between the helm and passenger seats is pretty large also. There is a large, built-in waterproof box, (with a drain plug), under the rear, center seat. There is also a pretty good bit of storage room underneath the rear port and starboard seats. Then, "under the hood," there are large storage areas on each side of the engine compartment. One thing that helped us was that there was a wake board rack added when the the wake board tower was installed. That helps to keep most of the kid's water toys up and out of the way when not in use.
I've noticed some marked improvements in storage design on the newer Tahoe models. There are lots of different configuration and design options, depending on whether you're looking at the standard Q4 model, or the Q4 Ski and Fish model, which will be set up a little bit differently.