The house is well suited for a large group. Our party had four adults and five kids, and we were very comfortable. The layout is pretty well configured with two bedrooms with en suite baths on the lower level (same level as the deck) and a master upstairs. The two baths downstairs was convenient for getting the kids out of the lake and into the shower after a fun day on the water. Shampoo, conditioner, and body wash were provided, which is a nice touch.
There's lots of dining space and the kitchen was comfortable for a few adults and kids milling around while making dinner. The house is well stocked with lots of towels and we also found that it had a lot of other kitchen items which we'd brought such as tin foil and paper towels. Not sure if that is stocked by the owner or left by previous guests, but it's nice to not have to travel with a full pantry.
As for the lake, we had a blast. The house is next door to a boat ramp which was great to get our jet ski and boat in/out of the water. We pulled the inner tube in the AM when the lake was nice and flat, and then spent the afternoons in the cove at the foot of the hill. We brought several floats (although there are quite a few at the house, too) and had a blast hanging out and swimming. The path to the water is pretty good, but wear good water shoes as there are tons of sticker burrs; the kids got into them when wearing flip flops.
In the evenings, the adults had the run of the upstairs, playing games and drinking without worrying about waking the kids who were all together in the bunk room. We also told them the hot tub was for grown-ups only and we enjoyed several hours there after a long day of chasing kids.
All in all we had a great time. Canyon Lake is very nice, the water was so blue and clear, it really impressed us. It's close to New Braunfels where we popped in to Landa Park and Krause's for dinner. Both were awesome and worth the 25 minute drive. Also, we pre-ordered our groceries at HEB prior to arriving and picked them up at the location off 46 & 337, making it super easy with two cars full of antsy kids and no worrying about having enough ice chest space to keep our Blue Bell cold. All in all, we had a fantastic time and would recommend it to others traveling with a group or a couple of families!