I absolutely love my Feelfree Moken 10 sit-on-top! My dog is 40lbs and there's plenty of room for her on the front. She loves to lie down and watch for ducks and geese as we paddle. Sit-on-top kayaks are great because they're super stable even if your pup tends to move around a bunch. I know that info doesn't help you with your space issue, but in the long run, I feel like it's worth the hassle. I'm not sure how an inflatable would do. I've got a friend with one and she takes her dog out with no problems, but her dog is only 10lbs. I'm not sure it would hold up to a larger dog.